Determine the amount of grams present in 3.25x1024 atoms of Lithium.

Which is true about the pH values of a 1.0 M solution of HCl (a strong acid) and a 1.0 M solution of HC2H3O2 (a weak acid)?

Neko [114]

Answer:

C. pH values are different because the $HC_2H_3O_2$ solution partially ionizes and the HCl solution ionizes 100 percent.

Explanation:

Strong acids are the acids which completely ionizes in the solution while weak acids are the acids which ionizes partially in the solution. They exists in equilibrium in the solution with their respective ions.

Thus, strong acids furnish greater concentration of protons as compared to weak acid when same concentration of both types are taken.

Also, pH is the negative of the logarithm of the hydrogen ions. Thus, hydrogen ion concentration for both acids are different and thus pH will be different.

4 0

3 years ago

Which statement best describes the properties of sucrose?

crimeas [40]

Answer:

D. They are different from the properties of carbon, oxygen, and hydrogen.

Step-by-step explanation:

Carbon, oxygen, and hydrogen are all elements.

Sucrose is a compound containing carbon, oxygen, and hydrogen. Its properties are different from those of its elements.

For example, carbon is a black solid, while oxygen and hydrogen are colourless gases. Sucrose is a white solid.

6 0

3 years ago

Read 2 more answers

the law of conversation of (mass/energy) states that the total mass before a chemical reaction is the same as the totally mass a

Nimfa-mama [501]

The law of conservation of mass says that matter cannot be created or destroyed by ordinary chemical or physical changes.

This means:

The mass will be the same before and after the chemical or physical change

There are the same number of each type of atom before and after the change

The total mass of all components of a chemical reaction or physical change can be measured before and after the change to demonstrate that the mass is constant.

Scientists believe that energy is conserved, like mass, during a physical or chemical change. The law of conservation of energy says that energy can be converted from one form to another, but it cannot be created or destroyed in ordinary chemical or physical changes.

Energy can be more challenging for scientists to keep track of during a chemical reaction than mass. Mass is able to be measured on a balance before and after the change, but scientists must use more advanced techniques to measure the energy in a system.

Energy is converted from one form to another during a chemical change.This energy is not created or destroyed; it is just converted from one form of energy to another during the chemical and physical changes that occur.

Physical Change: In a physical change, atoms are rearranged but remain in the same sample of matter. The same numbers of atoms are present before and after the change, and they have the same total mass. Atoms are spread farther apart or pushed closer together during a phase change. When a substance changes phases, the volume may change but the mass doesn't.

Chemical Change: In a chemical change, the original bonds are broken and new bonds are formed. The same atoms are present before and after a chemical change, they are just rearranged to make different compounds.

5 0

3 years ago

Anybody good at chemistry?

Luba_88 [7]

Answer:

Explanation:

1)

Given data:

Mass of lead = 25 g

Initial temperature = 40°C

Final temperature = 95°C

Cp = 0.0308 j/g.°C

Heat required = ?

Solution:

Specific heat capacity: Cp

It is the amount of heat required to raise the temperature of one gram of substance by one degree.

Formula:

Q = m.c. ΔT

Q = amount of heat absorbed or released

m = mass of given substance

c = specific heat capacity of substance

ΔT = change in temperature

ΔT = Final temperature = initial temperature

ΔT = 95°C - 40°C

ΔT = 55°C

Q = 25 g × 0.0308 j/g.°C × 55°C

Q = 42.35 j

2)

Given data:

Mass = 3.1 g

Initial temperature = 20°C

Final temperature = 100°C

Cp = 0.385 j/g.°C

Heat required = ?

Solution:

Specific heat capacity: Cp

It is the amount of heat required to raise the temperature of one gram of substance by one degree.

Formula:

Q = m.c. ΔT

Q = amount of heat absorbed or released

m = mass of given substance

c = specific heat capacity of substance

ΔT = change in temperature

ΔT = Final temperature = initial temperature

ΔT = 100°C - 20°C

ΔT = 80°C

Q = 3.1 g × 0.385 j/g.°C × 80°C

Q = 95.48 j

3)

Given data:

Mass of Al = ?

Initial temperature = 60°C

Final temperature = 30°C

Cp = 0.897 j/g.°C

Heat released = 120 j

Solution:

Specific heat capacity: Cp

It is the amount of heat required to raise the temperature of one gram of substance by one degree.

Formula:

Q = m.c. ΔT

Q = amount of heat absorbed or released

m = mass of given substance

c = specific heat capacity of substance

ΔT = change in temperature

ΔT = Final temperature = initial temperature

ΔT = 30°C - 60°C

ΔT = -30°C

120 j = m × 0.897 j/g.°C × -30°C

120 j = m × -26.91 j/g

m = 120 j / -26.91 j/g

m = 4.46 g

negative sign show heat is released.

4)

Given data:

Mass of ice = 1.5 g

Change in temperature = ?

Cp = 0.502 j/g.°C

Heat added= 30.0 j

Solution:

Specific heat capacity: Cp

It is the amount of heat required to raise the temperature of one gram of substance by one degree.

Formula:

Q = m.c. ΔT

Q = amount of heat absorbed or released

m = mass of given substance

c = specific heat capacity of substance

ΔT = change in temperature

ΔT = Final temperature = initial temperature

30.0 j = 1.5 g × 0.502 j/g.°C × ΔT

30.0 j = 0.753 j/°C × ΔT

30.0 j /0.753 j/°C = ΔT

39.84 °C = ΔT

3 0

3 years ago

What is the key element fountain all carbohydrates lipids proteins and nucleus acid

just olya [345]

Carbon is found in all four.

6 0

3 years ago