Which of the following best describes the change in Antarctic temperature from about 440,000 years ago to about 340,000 years ago?
A
The temperature increases by about 10 S
B
The temperature decreases by about 8°C.
С
The temperature increases by about 12°C and then decreases by about 12°C.
D
The temperature decreases by about 10°C and then increases by about 12°C.

Answer:

Q = 65 kJ

Explanation:

Given that,

Mass, m = 580 g

Initial temperature, [tex]T_i=25^{\circ} C[/tex]

Final temperature, [tex]T_f=150^{\circ} C[/tex]

The specific heat capacity for aluminum is 0.897 J/g°C

We need to find the heat added to the aluminium pan so that its heat raised to a temperature from 25°C to 150°C. It is given by :

[tex]Q=mc\Delta T\\\\Q=580\ g\times 0.897\ J/g^{\circ} C\times (150-25)^{\circ} C\\\\Q=65032.5\ J[/tex]

or

Q = 65.03 kJ

or

Q = 65 kJ

Hence, the heat added to the pan is 65 kJ.

Answer: Water is considered neutral because the concentration of hydrogen and hydroxide ions is the same

Explanation:

Answer:

24.32

Explanation:

From the question given above, the following data were obtained:

Isotope A:

Mass of A = 24

Abundance (A%) = 78.70%

Isotope B

Mass of B = 25

Abundance (B%) = 10.13%

Isotope C:

Mass of C = 26

Abundance (C%) = 11.17%

Average atomic mass of Mg =..?

The average atomic mass of Mg can be obtained as illustrated below:

Average atomic mass = [(Mass of A × A%)/100] + [(Mass of B × B%)/100] + [(Mass of C × C%)/100]

Average atomic mass = [(24 × 78.70)/100] + [(25 × 10.13)/100] + [(26 × 11.17)/100]

= 18.888 + 2.5325 + 2.9042

= 24.3247 ≈ 24.32

Therefore, the average atomic mass of magnesium (Mg) is 24.32

Answer:

4e-5 is the length in meters

Have a nice day! :)

A descriptive model of Earth's layers can be categorized as prototype model. Hence, option B is correct.

What is a descriptive model?

A descriptive model describes a system or other entity and its relationship to its environment.

The Earth has different compositional and mechanical layers. Compositional layers are determined by their components, while mechanical layers are determined by their physical properties.

The outermost solid layer of a rocky planet or natural satellite. Chemically distinct from the underlying mantle.

Hence, option B is correct.

Learn more about descriptive model here:

https://brainly.com/question/16988456

#SPJ2

Answer:

It is generally arranged by the atomic number

Explanation:

Answer:

0.2756 L

Explanation:

0.2756 L

Answer:

Because the have acquired energy from the heating process, that is why the start moving faster.

Explanation:

Hello.

In this case, since the  initial liquid water molecules have a certain energy content, which makes them move with the relatively medium velocity characteristic in liquid-phase substances, once energy starts being added, it is evidenced that the molecules acquire more energy which is able to make them move faster.

In such a way, since the initial water molecules velocity is marked by a medium range arrows, meaning that the molecules are moving not-so-fast, not-so-slow but the heated  water molecules are marked by longer arrows, meaning that they move faster, we infer that such velocity increase is due to the addition of heat due to the heating process from 20 °C to 96 °C (just before boiling).

Regards!

Molecular motion is the action of motion of the molecules or the particles in a specific direction. The molecules start moving faster due to the energy given by the heat.

The movement of the molecules or the particles in the system is affected by the temperature and the heat given to the system by the external source.

The initial molecules have relative speed and motion in the system and after the addition of the factors the energy of the motion of the particles gets affected.

When the temperature of the water in the beaker is increased then the average kinetic energy of the molecules also increases and hence the motion of the molecules increases.

The medium ranged arrows depict the average speed of the molecule movement in the medium, while the longer arrows suggest the fast-moving molecules of the water.

Therefore, the heat increases energy and in turn the molecular motion.

Learn more about molecular motion here:

https://brainly.com/question/14240663

Answer:

the marble would hit the floor first because the feather would be effected by air resistance

Answer:

You forgot to include the diagram use snipping tool to take a picture and upload it

Explanation:

Look for the ones with the same number of protons and different neutrons number

Answer:

3.35g of Ba3(PO4)2

Explanation:

The balanced chemical equation is given as;

3 BaCl2 + 2 Na3PO4 → 6 NaCl + Ba3(PO4)2

Fro the reaction;

3 mol of BaCl2 (624g) reacts wth 2 mol of Na3PO4 (327.88g) to form 1 mol of Ba3(PO4)2 (601.93g)

Since Na3PO4 is in excess, the limiting reactant is; BaCl2. It would determine how much of Ba3(PO4)2 is formed.

624g of BaCl2 = 601.93g of Ba3(PO4)2

4.512g of BaCl2= xg of Ba3(PO4)2

x = 4.512g * 601.93g / 624g

x = 3.35g of Ba3(PO4)2

The mass of barium phosphate synthesized is 3.612 g.

The equation of the reaction is;

3 BaCl2.2H2O + 2 Na3PO4.12 H2O → 6 NaCl + Ba3(PO4)2 + 14H2O

Molar mass of barium chloride dihydrate = 244.26 g/mol

The number of moles of barium chloride dihydrate =  4.512 g/244.26 g/mol

= 0.018 moles

From the balanced reaction equation shown;

If 3 moles of barium chloride dihydrate yields 1 mole of  barium phosphate

0.018 moles of  barium chloride dihydrate yields 0.018 moles × 1 mole/3 moles

= 0.006 mole of barium phosphate

Mass of barium phosphate = 602 g/mol × 0.006 mole

= 3.612 g

Learn more: https://brainly.com/question/9743981

Answer:

[CO2] > [N2] > [He]

Explanation:

The relative concentration of CO2, N2 and He depends on the solubility of each gas in water. The more soluble in water a gas is, the greater its concentration in aqueous solution.

Among the gases listed, CO2 is most soluble in water hence it is expected to have the greatest concentration in solution followed by N2. Helium gas is insoluble in water hence it has the least concentration in the aqueous solution.

Answer:

About 2.8

Explanation:

Answer:

Ultraviolet light.

Explanation:

Uranium is a natural radioactive chemical element with the chemical symbol "U" and an atomic number of 92. Uranium is used for generating nuclear fuels which are typically used in powering atomic bombs and nuclear reactors in the field of electricity generation.

When ignited, a uranium compound burns with a green flame. The wavelength of the light given off by this flame is greater than that of ultraviolet light which typically ranges from 100nm to 400nm. Where, nm is represents nanometer.

Basically, when ignited, a uranium compound burns with a green flame having a wavelength of 4.30 x 10^-7m to 5 x 10^-7m.

Answer:

1

Explanation:

Answer:

Explanation:

The acceleration of an object given it's mass and the force acting on it can be found by using the formula

[tex]a = \frac{f}{m} \\ [/tex]

where

a is the acceleration

f is the force

m is the mass

From the question

f = 20 N

m = 5 kg

We have

[tex]a = \frac{20}{5} \\ [/tex]

We have the final answer as

Hope this helps you

Answer:

Physical Properties

Explanation:

PHYSICAL PROPERTY

Answer:

phycical propertys

Explanation:

jut took the test got it right

Answer:

Option C. Change in enthalphy is negative, the reaction is exothermic.

Explanation:

In the profile diagram given in the question above, we can see clearly that the energy of the reactant (Hr) is higher than the energy of product (Hp).

Hence, the enthalpy change (ΔH) will be negative i.e

Enthalpy change (ΔH) = Energy of product (Hp) – Energy of reactant (Hr)

ΔH = Hp – Hr = negative (–) [since Hr is higher than Hp]

A reaction in which the enthalpy change (ΔH) is negative is termed exothermic reaction.

Answer:

They came from the element factories we call stars. Stars are mostly hydrogen throughout most of their lifespans. They are driven by massive and continuous thermonuclear reactions and gravity. ... This extra heat begins to fuse helium atoms into heavier elements like carbon and oxygen and gives new life to the star.

Explanation:

Answer:

They are both the same.

Explanation:

ONE POUND of feathers

ONE POUND of brick

Answer:

They are both the same

Explanation:

Even though feathers are lighter they are both 1 pound. Why do you have so many feathers?!?!?

Answer:

The rate of reaction remains the same, no change is observed

Explanation:

Remember that for an SN2 reaction, the rate of reaction depends both on the concentration of the alkyl halide and the concentration of the nucleophile.

Hence we can write; Rate = k [Alkyl halide][NaI]

This implies that if we half the concentration of the nucleophile and double the concentration of the alkyl halide, the rate of reaction just remains the same since the reaction is bimolecular and first order in both alkyl halide and nucleophile

Answer:

Explanation:

the SI unit of force. It is equal to the force that would give a mass of one kilogram an acceleration of one meter per second per second, and is equivalent to 100,000 dynes.

Answer:

Option C is correct option = 2.85×10⁻² lb/in³

Explanation:

Given data:

Density in g/mL = 0.789

Density in lb/in³ = ?

Solution:

It is given that,

2.54 cm = 1 in

2.205 lb = 1 kg   thus,

1 mL = 1 cm³

0.789 g/cm³ × 1 kg/ 1000 g × 2.205 lb/1 kg × (2.54 cm / 1in)³

2.85×10⁻² lb/in³

The density of liquid ethanol is 0.789 g/mL, which is equivalent to 0.0285 lb/in³.

A student measured the density of liquid ethanol to be 0.789 g/mL and we want to convert it to lb/in³. We will need a series of conversion factors.

A conversion factor is an arithmetical multiplier for converting a quantity expressed in one set of units into an equivalent expressed in another.

We will use the following conversion factors:

0.789 g/mL × (1 kg/1000 g) × (2.205 lb/1 kg) = 1.74 × 10⁻³ lb/mL

We will use the following conversion factors:

1.74 × 10⁻³ lb/mL × (1 mL/1 cm³) × (2.54 cm/1 in)³ = 0.0285 lb/in³

The density of liquid ethanol is 0.789 g/mL, which is equivalent to 0.0285 lb/in³.

Learn more about unit conversion here: https://brainly.com/question/13016491

The elements in the tall columns of the periodic table are called representative elements or main group elements. They exhibit similar chemical properties within their respective groups due to their shared number of valence electrons. The terms "valence elements," "atomic elements," and "period elements" are not commonly used or recognized in the context of the periodic table.

The correct answer is option  A.

The elements in the tall columns of the periodic table are called "A. Representative elements," also known as the "main group elements" or "group A elements." These elements are found in groups 1, 2, and 13 to 18 (excluding the transition metals) on the periodic table.

Representative elements are characterized by having similar chemical properties within their respective groups. This similarity arises from the fact that elements within the same group have the same number of valence electrons, which are the electrons in the outermost energy level of an atom. Valence electrons play a crucial role in determining the chemical behavior and reactivity of an element.

The representative elements include the alkali metals (Group 1), alkaline earth metals (Group 2), boron group (Group 13), carbon group (Group 14), nitrogen group (Group 15), oxygen group (Group 16), halogens (Group 17), and noble gases (Group 18). These elements exhibit a wide range of properties, from highly reactive metals to nonmetals and inert gases.

The term "valence elements" mentioned in option B is not commonly used in the context of the periodic table. Valence electrons are indeed significant in determining chemical properties, but they are not specific to the elements in the tall columns. Valence electrons are found in elements across the periodic table.

"Atomic elements" mentioned in option C is a vague term and does not specifically refer to the elements in the tall columns. All elements on the periodic table are atomic in nature, as they are composed of atoms.

"Period elements" mentioned in option D is not a recognized term in the context of the periodic table.

In conclusion, the elements in the tall columns of the periodic table are known as representative elements or main group elements. These elements exhibit similar chemical properties within their respective groups due to their shared number of valence electrons.

Therefore, from the options provided the correct one is A.

For more such information on: representative elements

https://brainly.com/question/17105472

#SPJ8

Answer:

Explanation:

Oxyacids are acid containing oxygen; they are also known as acid-alcohol or acid-phenol. As said earlier, the strength of these acids increases with increases in the polarity of these compounds. So, what makes the polarity is as a result of the electronegative substituents attached to it. Halogen family possesses the highest electronegativity in the periodic table, and electronegativity decreases down the group.

The ranking of the oxyacids in order of decreasing acid strength from strongest to weakest acid is:

HClO3 > . HClO2 > HClO > HBrO

Answer:

a

Explanation:

correct