Aldehydes are more reactive than ketones towards nucleophilic substitution because of both steric and electronic factors. Briefly explain in the textbook below.

Answers

Answer 1

The aldehyde is more reactive towards nucleophilic substitution than the ketone. The greater reactivity of aldehydes towards nucleophilic substitution is due to both of these factors.

Aldehydes are more reactive than ketones towards nucleophilic substitution because of both steric and electronic factors. Steric effects arise from the differences in the relative sizes of the aldehyde and ketone groups. The aldehyde group is smaller than the ketone group, which means that the electron density is higher around the aldehyde group. As a result, the aldehyde is more reactive towards nucleophilic substitution than the ketone. Electronic effects arise from the differences in the electron-withdrawing power of the aldehyde and ketone groups. The aldehyde group is more electron-withdrawing than the ketone group, which means that the electron density is lower around the aldehyde group. As a result, the aldehyde is more reactive towards nucleophilic substitution than the ketone. The greater reactivity of aldehydes towards nucleophilic substitution is due to both of these factors.

Learn more about nucleophilic substitution here:

https://brainly.com/question/30633020

#SPJ11


Related Questions

evidence concerning crystallized and fluid intelligence shows that

Answers

Evidence concerning crystallized and fluid intelligence shows the diverse nature of intellectual development.

Research on both crystallized and fluid intelligence suggests that there are different stages of intellectual development. Crystallized intelligence reflects the sum of knowledge, abilities, and experience obtained through education and life events. It includes vocabulary, factual knowledge, and problem-solving abilities that rely on previously learned information.

In contrast, the ability to reason logically, solve unexpected issues, and adapt to changing circumstances is referred to as fluid intelligence. It calls on abilities like pattern recognition, spatial imagery, and abstract reasoning. Studies have revealed that individuals can have varying levels of crystallized and fluid intelligence, and these skills can vary across different periods of life due to factors like education, environmental effects, and cognitive aging.

To know more about fluid intelligence here https://brainly.com/question/28139268

#SPJ4

What is the oxidation state of copper in Cu(C2H3O2)2? +2 -1 -2 +4 +1

Answers

The answer should be 5 cu

Classify the two amino acids below according to their effective polarity in proteins at pH=7.4. n= Nonpolar up = Uncharged polar cp= Charged polar 1. 2. Classify the two amino acids below according to their effective polarity in proteins at pH=7.4. n= Nonpolar up = Uncharged polar cp= Charged polar 1. 2. Cysteine (Cys or C ) Polarity

Answers

At pH = 7.4, Cysteine (Cys or C) can be classified as up = Uncharged polar. Cysteine is a polar amino acid with a sulfhydryl group.

Cysteine is a non-polar amino acid that is made up of an aliphatic side chain containing a sulfhydryl group (–SH). This polar cysteine side chain's polarity enables the formation of disulfide bridges with other cysteine side chains in other proteins and amino acids. The polar amino acid cysteine can form a disulfide bond with another cysteine in an amino acid chain, which gives a high degree of stability to the protein molecules. This amino acid contributes to the stabilization of protein molecules by forming hydrogen bonds and disulfide bonds. The electronegative sulfur atom is responsible for its polar nature. Cysteine can be classified as an uncharged polar amino acid at pH = 7.4. Nonpolar amino acids are hydrophobic (water-repelling) and do not interact well with water. Conversely, charged amino acids are hydrophilic (water-attracting) and interact well with water.

know more about Cysteine

https://brainly.com/question/31674455

#SPJ11

how to find rate of reaction experimentally of the reaction ? plz help

Answers

I think you would set the concentrations of the products over the concentrations over the reactants (excluding water because it’s a liquid). Since the question asks for you to describe, you don’t need to do any number calculations.

T/F. In an aqueous and diethyl ether extraction the aqueous will be the top layer?

Answers

The statement is True. In an aqueous and diethyl ether extraction, the aqueous layer will be the top layer. This is due to the difference in density between water and diethyl ether.

Water has a higher density compared to diethyl ether, which causes it to settle at the bottom layer. Diethyl ether, being less dense, will form the top layer. During the extraction process, immiscible solvents like water and diethyl ether are used. Since these solvents do not mix together, they form separate layers based on their densities. Water, being denser, will settle at the bottom while diethyl ether, being lighter, will float on top. This allows for the separation of compounds or substances that are preferentially soluble in either of the solvents. By carefully extracting the top or bottom layer, depending on the desired component, one can isolate specific compounds from a mixture.

To learn more about Diethyl ether, click here: brainly.com/question/14662255 #SPJ11

How many molecules are in 3.01 g of H2O

A. 0.167 molecules
B. 54.18 molecules
C. 1.01x10^23 molecules
D. 6.022x10^23

Answers

Answer:

Option C

Explanation:

No. of Molecules=(Given Weight/Molar weight)*Avagadro No.

Given weight of H2O=3.01g

Molar weight of H2O=18g

On applying the formula, we get:

No. of Molecules=(3.01/18)*6.023*10²³=1.01*10²³

. What is the total voltage of the circuit, if you install two D-cell batteries in a flashlight so that their positive ends are facing each other compared to If you installed the batteries with the positive and negative terminal facing each other

Answers

Answer:

0

Explanation:

A voltage makes the electric charges to move.

When we install a D - cell batteries in the flashlight with their positive ends facing each other, as compared to the batteries installed with their positive and negative terminals facing each other, the flashlight will not work as the total voltage across the two batteries will be zero.

13. The element with the following electron configuration [Kr] 4d105s25p2 belongs to
Group of answer choices
actinide.
metal.
transition element.
nonmetal.
lanthanide.
14. Which is a physical change?
Group of answer choices
KNO3 dissolves in water
A firecracker explodes
Popcorn pops when placed in a microwave
A nail rusts
A piece of wood is burned

Answers

The element with the following electron configuration [Kr] 4d105s25p2 belongs to transition element.

The given electron configuration belongs to an element with atomic number 52. It can be written as 1s22s22p63s23p63d104s24p64d105s25p2. It belongs to the transition element as the electrons are filled in d orbital. KNO3 dissolves in water is a physical change.A physical change refers to a change in the state or properties of matter without any modification in its composition. The given options that are physical change and rest is a chemical change.KNO3 dissolves in water is a physical change as the salt is still KNO3 and has not been modified into something else. It simply separated into smaller particles to mix uniformly with the solvent, which in this case is water.A firecracker explodes, when popcorn pops when placed in a microwave and a piece of wood is burned are all examples of chemical change.A nail rusts is also a chemical change.

Learn more about  electron configuration here:

https://brainly.com/question/29157546

#SPJ11

1. Assume that the top of your head has a surface area of 25cm x 25 cm. How many newtons of force push on your head at sea level? 2. If you estimate this area to be 100 in^2 what is the force in pounds

Answers

1. Approximately 6333.125 newtons of force push on your head at sea level. Given that the surface area of the top of your head is 25 cm x 25 cm = 625 cm², we can convert it to square meters:

To calculate the force pushing on your head at sea level, we need to use the formula for pressure:

Pressure = Force / Area

Area = 625 cm² × (1 m / 100 cm)^2 = 0.0625 m²

At sea level, the standard atmospheric pressure is approximately 101,325 Pascals (Pa) or 101.325 kilopascals (kPa). Therefore, the force pushing on your head can be calculated by multiplying the pressure by the area:

Force = Pressure × Area

Force = 101,325 Pa × 0.0625 m² = 6333.125 N (to three decimal places)

2.If the area of your head is estimated to be 100 square inches, approximately 1468.276 pounds of force push on your head at sea level.If we estimate the area to be 100 square inches, we can convert it to square meters:

Area = 100 in² × (0.0254 m / 1 in)^2 = 0.064516 m²

Using the same atmospheric pressure, the force pushing on your head can be calculated:

Force = Pressure × Area

Force = 101,325 Pa × 0.064516 m² = 6530.645 N (to three decimal places)

To convert this force into pounds, we can use the conversion factor of 1 N = 0.2248 lb:

Force in pounds = 6530.645 N × 0.2248 lb/N = 1468.276 lb (to three decimal places)

For more such questions on surface area.

https://brainly.com/question/16557677

#SPJ8

2.0 L of a gas is at STP. What is the new pressure in kPa if the volume changes to 10.5 L and the temperature and # of molecules remain constant?

Answers

Answer:

What is the new volume if the temperature is constant? V=2.50L. P = lookPa. P2=40k Pa. V2 = x. PV = P2 ... If a sample of gas occupies 6.8 L at 327°C

Normal values for chemistry tests on serous fluid are different from values obtained on serum.

a. True
b. False

Answers

a. True. Due to the differences in composition between serous fluid and serum, the normal values for chemistry tests can vary.

Serum refers to the liquid component of blood that remains after the blood has clotted and the clot has been removed.

On the other hand, serous fluid is a clear, watery fluid that is similar to serum and is found in body cavities such as the pleural, peritoneal, and pericardial cavities.

The composition of serous fluid can differ from serum due to various factors. When testing serous fluid, the values for chemistry tests such as electrolytes, proteins, enzymes, and other analytes may have different reference ranges compared to those obtained from serum testing. This is because the cellular and protein content of serous fluid is different from that of blood serum.

For example, the normal range for protein concentration in serum is generally higher compared to serous fluid due to the presence of fibrinogen and other proteins involved in clotting that are not present in serous fluid.

Due to the differences in composition between serous fluid and serum, the normal values for chemistry tests can vary. Therefore, it is important to use appropriate reference ranges specific to serous fluid when interpreting the results of chemistry tests on serous fluid samples.

To know more about serum visit:

https://brainly.com/question/30559641

#SPJ11

Define Transportation plants:

Define Respiration Plants:

Answers

Answer:

Define Transportation in plants: Transportation in plants is when the plant transports water and other mineral throughout the whole plant from the roots to the stem and finally specific parts of a plant.

Define Respiration In Plants: Is when plants use photosynthesis to make their own food to make energy for the plant's growth

Kathy is trying to conduct an experiment she wants an element that is
very reactive, which of these should she use?

Answers

we need choices to be able to answer this question


STEP BY STEP EXPLANATION:

How do you make the shadows of objects appear bigger on the screen​

Answers

Explanation:

Indoors, you can change the size of a shadow by moving your body or the object closer to or farther from the light.

Shadows grow bigger and fuzzier as the object moves closer to the light source, and smaller and sharper as the object moves farther away.

Emu
Sparrow
How are emus and sparrows alike?
A. Both birds build nests in trees.
B. Both birds are taller than humans.
C. Both birds catch small animals while flying.
U
D. Both birds have a beak for breaking apart food.

Answers

A for sure sparrows are like birds but sparrows build holes in trees and birds do nests in trees so for sure is a

HCl (aq) + NaOH (aq) = NaCl (aq) + H2O (l)

What type of reaction is the above?​

Answers

Answer:

Neutralization reaction

Explanation:

It is a reaction between an acid and a base

1. A student wants to find how many calories are in a peanut. Describe in detailed complete sentences how they can test this using a can with
150g of water and a thermometer.

Answers

Answer: 65 cal

Explanation: they have to find the weight of the peanuts on a scale and per grams. Then put them in water . You should be able to get the calories

Which of the following would produce the most fluid lipid bilayer?
Choose one:
A. phospholipids with fully saturated tails of 20 carbon atoms
B. phospholipids with fully saturated tails of 18 carbon atoms
C. large amounts of cholesterol
D. phospholipids with tails of 18 carbon atoms and two double bonds
E. phospholipids with tails of 20 carbon atoms and two double bonds

Answers

Phospholipids with tails of 18 carbon atoms and two double bonds would   produce the most fluid lipid bilayer

Option (D) is correct.

The fluidity of a lipid bilayer is influenced by the composition of the phospholipids that make up the membrane. The presence of unsaturated fatty acid tails, indicated by the presence of double bonds, increases the fluidity of the lipid bilayer.

phospholipids with tails of 18 carbon atoms and two double bonds, would produce the most fluid lipid bilayer among the given choices. The presence of double bonds in the fatty acid tails introduces kinks in the hydrocarbon chains, which prevent them from packing tightly together. This increases the fluidity of the lipid bilayer by allowing the phospholipids to move more easily.

Therefore, the correct option is (D).

To learn more about Phospholipids  here

https://brainly.com/question/30414619

#SPJ4

Identify the parts of a wave using the illustration and the function below.

Answers

Answer: 1. Crest  2. Trough 3. Wave Length 4. Amplitude

Explanation:

The energy needed to overcome intermolecular forces is called?

Answers

Answer:

vaporization.

Explanation:

PLSSSSSS ANSWERRRRR???

Answers

Answer:

( j ) should be the correct option because atomic number of fluorine is 9 so, no. of electrons and protons should be same I.e. 9

A 25.0 mL sample of 0.150M hydrocyanic acid is titrated with a 0.150M NaOH solution. What is the pH before any base is added? The Ka of hydrocyanic acid is 4.9 X 10^-10.

Answers

The pH before any base is added to the hydrocyanic acid solution is approximately 0.82.

Before any base is added, the pH of the hydrocyanic acid solution can be calculated using the Ka value and the initial concentration of the acid. The pH of a solution is determined by the concentration of H+ ions present. Hydrocyanic acid (HCN) is a weak acid that partially dissociates in water. The dissociation can be represented as follows: HCN ⇌ H+ + CN-. The Ka value of hydrocyanic acid (HCN) is given as 4.9 x 10^-10.

To find the pH before any base is added, we can assume that the dissociation of HCN is negligible compared to its initial concentration. Therefore, the concentration of H+ ions can be considered equal to the initial concentration of HCN. Using the given concentration of hydrocyanic acid (0.150M), we can calculate the pH by taking the negative logarithm (pH = -log[H+]). The concentration of H+ ions is 0.150M, and thus the pH is determined as the negative logarithm of 0.150, which is approximately 0.82.

To learn more about concentration, click here:

brainly.com/question/3045247

#SPJ11

Pls help if you can, Thx! Describe ozone creation and loss in the ozone layer. Does one occur more than the other?

Answers

They Ozone was created millions of years ago from a natural process frozen in ice during the ice age, the gases that make up the ozone layer were formed naturally from a reaction of ultraviolet radiation and molecular oxygen which was frozen in the ice during the time of the ice age was released over years as the ice melted. However over hundreds of years of mechanical evolution and other man based forms of carbon production the ozone layer has decreased much faster than it has been repaired, meaning loss of the ozone layer occurs more often

Ozone was created millions of years ago from a natural process frozen in ice during the ice age, the gases that make up the ozone layer were formed naturally from oxygen atoms accompanied by a reaction of ultraviolet radiation and molecular oxygen which was frozen in the ice during the time of the ice age was released over years as the ice melted.

What is an atom?

An atom is defined as the smallest unit of matter which forms an element. Every form of matter whether solid,liquid , gas consists of atoms . Each atom has a nucleus which is composed of protons and neutrons and shells in which the electrons revolve.

The protons are positively charged and neutrons are neutral and hence the nucleus is positively charged. The electrons which revolve around the nucleus are negatively charged and hence the atom as a whole is neutral and stable due to presence of oppositely charged particles.

Atoms of the same element are similar as they have number of sub- atomic particles which on combination do not alter the chemical properties of the substances.

Learn more about atom,here:

https://brainly.com/question/13654549

#SPJ6

What would be the mass, in grams, of 3.50 x 1025 molecules of chlorine?

Show your work

Answers

Answer:

2059.645g Cl

Explanation:

A mole of any element contains 6.022e23 molecules, so we will divide the given amount of molecules by 6.022e23.

3.5e25 / 6.022e23 = 5.81e1

5.81e1 = 58.1 mol Cl

Now that we have found the amount of moles of Chlorine, we will multiply the number of moles by the molar mass of Chlorine, which is 35.45g/mol.

35.45(58.1) = 2059.645g Cl


Please help me ASAP I’m almost done.

Answers

Answer:

i think the answer is c

Explanation:

sorry if im wrong i am most likely wrong but ye

HELP ASAP 30 POINTS
IS THIS CORRECT?

Answers

answer: yes I believe so

explain: I just think it is I have done this before

yes, it is correct . hope i helped

the standard heat of formation for NO2 is 33.2. kj/mol. how much energy is required to form 140.0g of NO2 from its respective elements in kj

Answers

Approximately 100.916 kJ of energy is required to form 140.0 g of NO2 from its respective elements.

The energy required to form 140.0 g of NO2 from its respective elements can be calculated using the standard heat of formation and stoichiometry. First, we need to determine the number of moles of NO2 in 140.0 g. The molar mass of NO2 is 46.01 g/mol, so the number of moles is calculated as:

moles of NO2 = mass of NO2 / molar mass of NO2 = 140.0 g / 46.01 g/mol ≈ 3.043 mol

Next, we multiply the number of moles by the standard heat of formation, which is given as 33.2 kJ/mol:

energy required = moles of NO2 × standard heat of formation

= 3.043 mol × 33.2 kJ/mol

≈ 100.916 kJ

To learn more about molar mass, click here: brainly.com/question/12127540

#SPJ11

what is the volume of 9.783 x 1023 atoms of he at 9.25 atm and 512k?

Answers

The volume of 9.783 x 10^23 atoms of helium at 9.25 atm and 512 K is approximately 1.97 liters.

To calculate the volume of gas, we can use the ideal gas law equation:

PV = nRT

Where:

P is the pressure (in atmospheres)

V is the volume (in liters)

n is the number of moles

R is the ideal gas constant (0.0821 L·atm/(mol·K))

T is the temperature (in Kelvin)

Given:

Number of atoms of helium (n) = 9.783 x 10^23 atoms

Pressure (P) = 9.25 atm

Temperature (T) = 512 K

First, we need to convert the number of helium atoms to moles. Since 1 mole contains Avogadro's number (6.022 x 10^23) of particles:

Number of moles (n) = Number of atoms / Avogadro's number

Number of moles (n) = 9.783 x 10^23 atoms / 6.022 x 10^23

Number of moles (n) ≈ 1.625 moles

Now, we can rearrange the ideal gas law equation to solve for the volume (V):

V = (nRT) / P

V = (1.625 moles * 0.0821 L·atm/(mol·K) * 512 K) / 9.25 atm

V ≈ 1.97 liters

Therefore, the volume of 9.783 x 10^23 atoms of helium at 9.25 atm and 512 K is approximately 1.97 liters.

To learn more about ideal gas law equation, Visit:

https://brainly.com/question/27870704

#SPJ11

A student dilutes 50.0 mL of a 0.10 mol/L to 0.010 mol/L. Which statement is true?​

Answers

The total amount of solute decreases.

how do hydrogen fuel cells and fossil fuels produce energy?

Answers

Answer:

The hydrogen reacts with oxygen across an electrochemical cell

Explanation:

Other Questions
How do you really feel about writing or English classes? Why? . (Think about the last time that you wrote, how you feel about the act of writing, and how you feel about reading: explain what you feel is the scariest or most dreadful thing about writing and if there is an area of writing or English that you feel more confident in, and any areas where you may want to improve your skills with writing.) 2. What do you think about brainstorming before writing? For this assignments, what type of prewriting or brainstorming did you use to generate ideas, and why did you choose that method? (Explore the brainstorming methods you have used in the past, your thoughts about these brainstorming methods, whether or not these methods have helped you, and which types of brainstorming you would like to try in the future.) 3. Why do you think that so many students struggle with grammar, citations, and formatting? Now that you have had time to study with MLA, how do you feel about citations and formatting? (Think about whether or not you feel that grammar rules were more difficult to learn or citation and formatting rules and the reasons that students struggle with citations; explore any difficulties that you had and any aspects or resources that could make citations or formatting easier to understand or master.) 4. Based on the unit readings and resources, and your level of success with the quizzes, how do you plan to adjust your own personal composing process in order to be successful in this course? . (Think about how you currently study and complete assignments, the activities that may hinder your success as a student such as procrastination or watching TV while working, and the strategies outlined in the unit resources that may improve your writing; there is not right or wrong strategy: developing a personal composing process takes time and will be unique to your learning style.) match the following function of sales management with tasks involved with each. The president of Doerman Distributors, Inc., believes that 31% of the firms orders come from first-time customers. A random sample of 101 orders will be used to estimate the proportion of first-time customers.1. What is the probability that the sample proportion will be between 0.21 and 0.41?7. What is the probability that the sample proportion will be between 0.26 and 0.36? Sheridan Company issued $1,240,000, 12-year bonds. It agreed to make annual deposits of $99,000 to a fund (called a sinking fund), which will be used to pay off the principal amount of the bond at the end of 12 years. The deposits are made at the end of each year into an account paying 6% annual interest. (For calculation purposes, use 5 decimal places as displayed in the factor table provided.) What amount will be in the sinking fund at the end of 12 years? (Round answer to 2 decimal places, e.g. 25.75.) Amount in the sinking fund $____ As amazing as it seems, it is possible to be learning without a change in performance. TRUE/False .Which of the following should not be included in the acquisition cost of the equipment:A. Unclaimed cash discount.B. Duties paid to customs when the equipment is imported.C. The shipping cost of the equipment to the factory.D. Interest expense on borrowings to purchase equipment. A simple random sample of 20 new automobile models yielded the data shown to the right on fuel tank capacity, in gallons13.212.118.921.517.321.115.312.420.816.813.619.921.619.612.520.622.320.822.517.6a. Find a point estimate for the mean fuel tank capacity for all new automobile models. (Note: xi=360.4)A point estimate is _____ gallons.(Type an integer or a decimal. Do not round.)b. Determine 95.44 % confidence interval for the mean fuel tank capacity of all new automobile models. Assume =3.60 gallons.The 95.44 %confidence interval is from ____ gallons to ______ gallons.(Do not round until the final answer. Then round to two decimal places as needed.) a primary oocyte has 14 pairs of sister chromatids. how many dna molecules will a secondary oocyte have undergoing anaphase ii of meiosis? A market is described by the following supply and demand curves:QS = 2PQD = 300 Pa) Solve for the equilibrium price and quantity.b) If the government imposes a price ceiling of $90, does a shortage or surplus (or neither) develop?What are the price, quantity supplied, quantity demanded and size of the shortage or surplus?c) If the government imposes a price floor of $90, does a shortage or surplus (or neither) develop? What are the price, quantity supplied, quantity demanded and size of the shortage or surplus?d) Instead of a price control, the government levies a tax on producers of $30. As a result, the new supply curve is QS = 2(P 30).Does a shortage or surplus (or neither) develop? What are the price, quantity supplied, quantity demanded and size of the shortage or surplus? Consider the following POPULATION of test scores{98, 75, 78, 83, 67, 94, 91, 78, 62, 92}a) Find the mean , , the variance, 2 and the standard deviationb) Apply the Empirical Rule at the 95% levelc) What percentage of these Test Scores actually lie within the interval found inpart (b) evaluate sum in closed formf(x) = sin x + 1/3 sin 2x + 1/5 sin 3x + .... Compare and contrast two forms of project management methodologies by answering the following questions:- How are the methodologies similar?- How are they different?- When might you choose one methodology over the other?- How do enterprise goals and business environment impact what methodology is used? LINEAR DIOPHANTINE EQUATIONS 1) Find all integral solutions of the linear Diophantine equations 6x + 11y = 41 = Which of the following is not a risk typically associated with outsourcing. O Increased employee morale O Increased reliance on 3rd parties O Poor service O Failure to realize expected savingsORFI h You are taking a test with multiple choice questions for which you have mastered 70% of the course material. Assume you have a 0.7 chance of knowing the answer to a random test question, and that if you don't know the answer to a question then you randomly select among the four answer choices. Finally, assume that this holds for each question, independent of the others. Each question accounts for equal percentage of the total sco- re. (a) What is your expected score (in percentage%) on the exam?! (b) If the test has 10 questions, what is the probability you score 90% or higher? (c) What is the probability you get the first 6 questions on the exam correct? (d Suppose you need a 90% score to keep your scholarship. Would you rather have a test with 10 questions or a much larger number of questions? Please provide a reason use the english and metric equivalents provided at the right, along with dimensional analysis, to convert the given measurement to the unit indicated. dm to in.english and metric equivalents1 in = 2.54 cm1 ft = 30.48 cm1 yd ~0.9 m1 mi ~0.6 kmin the english system. 30 dm is equivalent to ____ in ( round to the nearest hundredth as needed) use dimensional analysis to show that the units of the process transconductance parameter k'n are a/v2. what are the dimensions of the mosfet transconductance parameter ? The entire market for a good is 1,000 units, and the minimum efficient scale is 5 units. Which of the following terms accurately describes this market?InefficientConcentratedFragmentedMonopolizedDiseconomy what are the key points of contention on this topic death with dignity Mark and Spencer Limited issued a semi-annual interest rate bond with a face value of $1,000. The bond is currently trading at $1,028.50, with 5.0 percent coupon rate. If the yield to maturity is 5.2 percent, calculate the number of years to maturity of Mark and Spencers bond.a. 8.28 yearsb. 8.80 yearsc. 10.80 yearsd. 10.94 years