Answer:
[tex]B_3H_6N_3[/tex]
Explanation:
Hello there!
In this case, since the mass percentages in a compound which is wanted to know the molecular formula, can be assumed to be the masses, we first need to compute the moles they have in the formula unit:
[tex]n_B=40.29gB*\frac{1molB}{10.811gB} =3.73molB\\\\n_H=7.51gH*\frac{1molH}{1.01gH} =7.44molH\\\\n_N=52.20gN*\frac{1molN}{14.01gN} =3.73molN[/tex]
Next, we divide each moles by the fewest ones (3.73 mol) in order to find the subscript in the empirical formula first:
[tex]B:\frac{3.73}{3.73}=1 \\\\H:\frac{7.44}{3.73}=2\\\\N:\frac{3.73}{3.73}=1[/tex]
Then, the empirical formula is BH2N whose molar mass is 26.83 g/mol, so the ratio of molecular to empirical is 80.50/26.83=3; therefore, the molecular formula is three times the empirical one:
[tex]B_3H_6N_3[/tex]
Best regards!
What Mass of glucose is
needed to prepare 235mL of 22% w/v glucose?
Answer: 8 grams of glucose are needed to prepare 400. ml of a 2.0%(m/v) glucose solution. 8 grams of glucose are needed to prepare 400.Oct 6, 2017
Answer:
8 grams of glucose are needed to prepare 400. ml of a 2.0%(m/v) glucose solution. 8 grams of glucose are needed to prepare 400
Explanation:
Plz help me!!!!plzzz!
Answer:
A
Explanation:
Since the new moon is behind the earth, It is sun, earth, moon
Where is the arctic tundra biome found?
Use this website to answer the question: https://thewildclassroom.com/biomes/artictundra-2/
Question 2 options:
Almost entirely in the Northern Hemisphere, from 60 to 70 degrees latitude North.
In tropical and subtropical latitudes
In high altitudes
Within tropical and subtropical latitudes
Answer:
In high altitudes
Explanation:
hope it helps you
The artic tundra biome is found in high altitudes.
What is arctic tundra biome?Artic tundra biome is the northernmost biome, which covers the land of the arctics with the ice caps.
Climate of this Artic tundra biome is almost cold means the temperature in winter season of this region is about -34 degree celsius and temperature in summer season of this region is about 3 - 12 degree celsius. And it observed generalyy on the northen side.
Hence correct option is (C).
To know more about Artic tundra biome, visit the below link:
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PLEASE HELP!!! I will mark brainliest I am really struggling with these problems
Answer:
21883.75 Joules are required to melt the ice!
Cars are the leading cause of____
1. carbon dioxide
2. nitrogen oxide
3.carbon monoxide
pollution
Answer:
nitrogen oxide
Explanation:
which wet land is known for the large trees in the water known as bottomland hardwoods?
A. Central Texas
B.South Texas
C. East texas
A balloon originally has 0.100 moles of helium and has a volume of 0.500 L. If 0.590 grams of He are added to the balloon, what will the new volume be, in L? (Assume temperature and pressure do not change.)
Answer:
1.24 L
Explanation:
Avogadro's Law
[tex]\frac{V_{1} }{n_{1} } = \frac{V_{2} }{n_{2} }[/tex]
Convert 0.590 g of He to moles.
0.590 g x (1 mol/4.00 g) = 0.1475 mol He
Add 0.1475 mol to 0.100 mol since the initial moles (n1) increases by this amount.
0.100 mol + 0.1475 mol = 0.2475 mol He
This will represent the final moles (n2)
The initial volume is given, 0.500 L. Plug in the values.
[tex]\frac{0.500 L}{0.100 mol} = \frac{V_{2} }{0.2465 mol}[/tex]
[tex]V_{2} = \frac{(0.500 L)(0.2475 mol)}{(0.100 mol)} \\V_{2} = 1.2375\\V_{2} = 1.24 L[/tex]
Taking into account the Avogadro's law, the new volume will be 1.24 L.
Avogadro's law establishes the relationship between the amount of gas and its volume when the temperature and pressure are held constant. Remember that the amount of gas is measured in moles.
This law states that constant pressure and temperature, the same amount of gas has the same volume regardless of the chemical element that forms it.
On the other hand, Avogadro's law establishes that the volume is directly proportional to the quantity of gas: if the quantity of gas increases, the volume will increase; whereas if the amount of gas decreases, the volume decreases.
Mathematically, this law states that the ratio between the volume and the quantity of gas is constant:
[tex]\frac{V}{n} =k[/tex]
Assuming that you have an initial state 1 and the conditions are modified to a final state 2, it is true:
[tex]\frac{V1}{n1} =\frac{V2}{n2}[/tex]
In this case, being the molar mass of He 4 g/mole, 0.590 grams of He are contained in the following amount of moles:
[tex]0.590 gramsx\frac{1 mole}{4 grams} =0.1475 moles[/tex]
Then, you know:
V1= 0.500 Ln1= 0.100 molesV2= ?n2= 0.100 mol + 0.1475 mol = 0.2475 mol He because 0.590 grams are added, this is 0.1475 moles, of He to the balloonReplacing in Avogadro's Law:
[tex]\frac{0.500 L}{0.100 moles} =\frac{V2}{0.2475 moles}[/tex]
Solving:
[tex]V2=0.2475 molesx\frac{0.500 L}{0.100 moles}[/tex]
V2= 1.2375 L≅ 1.24 L
Finally, the new volume will be 1.24 L.
Learn more:
https://brainly.com/question/15737923?referrer=searchResultshttps://brainly.com/question/4147359?referrer=searchResultsMs. Fremont spent last weekend grading tests . If she spent 4 min on each test , how many hours did it take her to grade all 74 tests ?
Answer:
about 5 hours
Explanation:
When doing this problem you mmust mulitiply 4 x 74 and divide the answer by 60 because 60=1 hour.
In an electrical circuit, the presence of a resistor limits the current and prevents
damage related to short circuits.
True or
False
Which statement is completely accurate? O Atoms of the same element always have different numbers of neutrons. O Atoms of the same element can have neutrons but exist without protons. O Atoms of the same element always have different atomic weights. O Atoms of the same element can have different numbers of neutrons.
Answer: last one is right
Explanation: atoms of same element have always same number of protons but may have several isotopes which have different number of neutrons.
A chemistry student is given 3.00 L of a clear aqueous solution at 17 C . He is told an unknown amount of a certain compound X is dissolved in the solution. The student allows the solution to cool to 17 C . The solution remains clear. He then evaporates all of the water under vacuum. A precipitate remains. The student washes, dries and weighs the precipitate. It weighs 0.15 kg . Using the above information can you calculate the solubility, X, in water at 17 C.
Answer:
The right approach is "50 g/l".
Explanation:
The given values are:
Mass or solute or precipitation,
= 0.15 kg
on converting it into "g", we get
= [tex]0.15 \ kg\times \frac{1000 \ g}{1 \ kg}[/tex]
= [tex]150 \ g[/tex]
Volume of solution,
= 3.00 L
Now,
The solubility of X will be:
= [tex]\frac{Mass \ of \ X}{Volume \ of \ solution}[/tex]
On substituting the values, we get
= [tex]\frac{150}{3}[/tex]
= [tex]50 \ g /l[/tex]
What are the two types of bonding we have studied?
a. Metallic and covalent
b. Covalent and ionic
c. lonic and metallic
d. Molecular and metallic
The first three half live of a chemical 2 / 2 reaction are as follows 44 min, 22 min, 11 min. What is the order the reaction?
How many moles are present when there are 1.00 * 10 to the 26 power
Answer:
166.11 mol
Explanation:
I hope you mean molecules
1 mol of anything is 6.02 * 10^23
x mol of anything is 1 * 10^26
1/x = 6.02 * 10^23/1 * 10^26 Cross multiply
1 * 1*10^26 = 6.02*10^23 * x Divide by 6.02*10^23
1*10^26/6.02 * 10^23 = x
x = 166.11 mol
Select the correct answer.
For Al, its atomic number is 13 and its mass number is 27. How many neutrons does it have?
Ο Α. .
13
ОВ.
14
26
OD
27
O E
40
Answer:
B.) 14
Explanation:
27-13=14 neutrons
The acceleration of a baseball after it is hit by a bat depends on the mass of the ball and the net force on the ball. This example best illustrates which law?
a
Newton's law of universal gravitation.
b
Newton's first law of motion.
c
Newton's third law of motion.
d
Newton's second law of motion.
what charge does nitrogen have
Answer:
3-
Explanation:
Due today!
If you weigh 200 lbs on Mars how much would you weigh on Earth
Answer:
75.88 pounds (or 75 pounds and 14 ounces.)
PLEASE HELP!
A piece of metal is heated to a temperature of 50.0°C and then placed in a calorimeter containing 50.0 g of water at 27.0°C. The water temperature increases to 35.0°C. How many joules of heat were transferred from the metal to the water? (Cwater = 4.18J/g•°C)
Answer: 1672 Joules
Explanation:
The quantity of heat required to raise the temperature of a substance by one degree Celsius is called the specific heat capacity.
[tex]Q=m\times c\times \Delta T[/tex]
Q = Heat absorbed by water = ?
c = heat capacity of water = [tex]4.18 J/g^0C[/tex]
Initial temperature of the water = [tex]T_i[/tex] = [tex]27^0C[/tex]
Final temperature of the water = [tex]T_f[/tex] = [tex]35^0C[/tex]
Change in temperature ,[tex]\Delta T=T_f-T_i=(35.0-27.0)^0C=8.0^0C[/tex]
Putting in the values, we get:
[tex]Q=50.0g\times 4.18J/g^0C\times 8.0^0C=1672J[/tex]
As heat absorbed by water is equal to the heat released by metal, the Joules of heat transferred are 1672 Joules
The daily dose for aspirin recommended by doctors is 81 mg/ day to reduce heart disease. a) In a week how many milligrams are administered? b) Convert the "weekly "milligrams to grams.
Answer:
a)567mg
b)0.567 grams
Explanation:
There are 7 days in a week, so we multiply the number of weeks by the number of daily dosage.
81mg*7=567mg
1 gram is 1000 mg
we divide 567 by 1000 to get the value in grams
A cylinder contains hydrogen gas at 20 atm. How many balloons of 500 ml capacity can be filled up completely from the gas cylinder at the external atmospheric pressure of 640 mm of Hg at constant temperature? The volume of empty cylinder is 20 liters.
Answer:
950 balloons
Explanation:
P1 = pressure inside cylinder = 20atm
P2 = pressure outside = 640mmhg = 0.842105 atm
V1= volume of cylinder =20L = 20,000 ml
V2 = volume of a single balloon= 500ml
n = number of balloons
[tex]P_{1}V_{1} =n P_{2}V_{2}\\20* 20000 =n 0.842105 * 500\\n = 950.[/tex]
b) Name three substances which can undergo sublimation and deposition respectively
solid carbon dioxide, iodine, arsenic, and naphthalene
Explanation:
Examples of substances that undergo sublimation
Examples of solids that sublime are dry ice (solid carbon dioxide), iodine, arsenic, and naphthalene (the stuff mothballs are made of).
The dropping off of sediments in a new place is called
A hydrogen fuel cell is an electrochemical reactor in which oxygen and hydrogen gas are reacted to produce energy. Rather than combusting hydrogen in the presence of oxygen, the overall reaction (1/2) O2 H2 → H2O is actually carried out as two `half-reactions’ occurring at separate electrodes. To complete the reaction, this forces electrons to pass through an external circuit from one electrode to the other, and this current can be used to do work; e.g., by driving a motor. Typical operating conditions for a solid-oxide fuel cell are 500-900 C and 5-15 bar. Consider a fuel cell in which a pure oxygen stream and a pure hydrogen stream enter at 11 bar and 700 C with stoichiometric flowrates. Assume that these reactants are consumed completely, and that the water generated by the reaction leaves in a third stream at the same T and P. Assume that the fuel cell operates at steady-state with a uniform temperature of 700 C. a) Write simplified first and
Answer:
(d) Why is the fuel cell in Question (c) described as an alkaline fuel cell? (e) Another type of fuel cell uses methanol instead of hydrogen.
Explanation:
Raw milk is stored at a dairy farm in a refrigerated cylindrical vat 6.50 feet wide and 12.5 feet high. If the vat contains 3.3 × 10² ft³ of milk, how many kg of milk does the vat contain, given that raw milk has a density of 1030 kg/m3?
Answer:
11.02 kg kg
Explanation:
From the question,
Density = Mass/Volume
D = m/v.................. Equation 1
Let D = Density of milk in the vat, m = mass of the milk in the vat, v = volume of the milk in the vat.
Make m the subject of the equation
m = D/v................ Equation 2
Given: D = 1030 kg/m³, v = 3.3×10² ft³ = 330×0.2832 = 93.456 m²
Substitute these values into equation 4
m = 1030/93.456
m = 11.02 kg
Density is the mass of the substance present in the unit of the volume or can be said to be equal to the ratio of the mass and the volume of the given substance or object.
31,576.71 kg of milk is present in the vat.
How to calculate the mass of the milk?Given,
Density = [tex]1030\rm \; kg/m^{3}[/tex]Volume (V) = [tex]3.3\times 10^{2} \;\rm ft^{3}[/tex]The volume in cubic feet will be converted in [tex]\rm m^{2}[/tex] as,
1 cubic feet = 0.0929 [tex]\rm m^{2}[/tex]
[tex]\begin{aligned}\rm V &= 330 \times 0.0929 \\\rm V &= 30.657\;\rm m^{2}\end{aligned}[/tex]
The formula for calculating mass form density and volume is:
[tex]\begin{aligned}\;\rm Mass (m) &= \rm Density \times Volume (V)\\\\\rm m &= 1030 \rm kg/m^{3} \times 30.657\rm m^{2}\\\\\rm m &= 31,576.71 \rm kg \end{aligned}[/tex]
Therefore, 31,576.71 kg is the mass.
Learn more about density and mass here:
https://brainly.com/question/2499453
what does dry ashing mean
Which type of cell can have a flagellum or cilia
Answer:
Both prokaryotic and eukaryotic cells contain structures known as cilia and flagella. These extensions from the cell surface aid in cell movement. They also help to move substances around cells and direct the flow of substances along tracts. Cilia and flagella are formed from specialized groupings of microtubules called basal bodies.
Explanation:
Which of the following is a period 4 representative element?
A. C
B. An
C. Ti
D. K
[tex]\huge{\mathbb{\tt { QUESTION↓}}}[/tex]
Which of the following is a period 4 representative element?
O A. C
O B. An
O C. Ti
O D. K
[tex]\huge{\mathbb{\tt {ANSWER↓}}}[/tex]
[tex]\color{blue}{\tt {A.C ( Carbon )}}[/tex]
[tex]{\boxed{\boxed{\tt { WHAT \: IS \: CARBON?}}}}[/tex]
Carbon (from Latin: carbo "coal") is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalen - making four electrons available to form covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon makes up only about 0.025 percent of Earth's crust.#CarryOnLearning
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→XxKim02xXPlz help me I am timed well mark brainliest if correct!!
Question 5
Complete the following analogy:
Reflection nebulae : blue :: emission nebula:
Greenish-blue
Yellow
Red
Pinkish-red
Answer:
That one is tricky but i would say yellow
Explanation: