All categories

3 years ago

How do I know what to do and can you help me because I really need it I am failing chemistry because it is too hard.

Chemistry

1 answer:

Arlecino [84]3 years ago

4 0

Exothermic:

An Exothermic reaction is a chemical reaction that expels energy in the form of heat/light. Everything a Endothermic does not do. Pretty simple for this one

reactants → products + energy.

For future reference - Exo means release, thermic means heat.

Energy is a Reactant

_________________________________________________________

Endothermic:

An Endothermic reaction essentially is draining the heat energy from anything its its surroundings. Usually its just heat but can also be salt dissolving it water or ice melting. Another example would be frost on your windshield evaporating.

It is the exact opposite of an Exothermic reaction.

Energy is a Product

You might be interested in

A solution was prepared by dissolving 0.800 g of sulfur S8, in 100.0 g of acetic acid, HC2H3O2. Calculate the freezing point and

Romashka [77]

Answer: The freezing point of solution is 16.5°C and the boiling point of solution is 118.2°C

Explanation:

To calculate the molality of solution, we use the equation:

$Molality=\frac{m_{solute}\times 1000}{M_{solute}\times W_{solvent}\text{ in grams}}$

Where,

$m_{solute}$ = Given mass of solute $(S_8)$ = 0.800 g

$M_{solute}$ = Molar mass of solute $(S-8)$ = 256.52 g/mol

$W_{solvent}$ = Mass of solvent (acetic acid) = 100.0 g

Putting values in above equation, we get:

$\text{Molality of solution}=\frac{0.800\times 1000}{256.52\times 100.0}\\\\\text{Molality of solution}=0.0312m$

Calculation for freezing point of solution:

Depression in freezing point is defined as the difference in the freezing point of water and freezing point of solution.

$\Delta T_f=\text{freezing point of acetic acid}-\text{Freezing point of solution}$

To calculate the depression in freezing point, we use the equation:

$\Delta T_f=iK_fm$

or,

$\text{Freezing point of acetic acid}-\text{Freezing point of solution}=iK_fm$

where,

Freezing point of acetic acid = 16.6°C

i = Vant hoff factor = 1 (for non-electrolyte)

$K_f$ = molal freezing point depression constant = 3.59°C/m

m = molality of solution = 0.0312 m

Putting values in above equation, we get:

$16.6^oC-\text{freezing point of solution}=1\times 3.59^oC/m\times 0.0312m\\\\\text{Freezing point of solution}=16.5^oC$

Hence, the freezing point of solution is 16.5°C

Calculation for boiling point of solution:

Elevation in boiling point is defined as the difference in the boiling point of solution and freezing point of pure solution.

The equation used to calculate elevation in boiling point follows:

$\Delta T_b=\text{Boiling point of solution}-\text{Boiling point of acetic acid}$

To calculate the elevation in boiling point, we use the equation:

$\Delta T_b=iK_bm$

or,

$\text{Boiling point of solution}-\text{Boiling point of acetic acid}=iK_fm$

where,

Boiling point of acetic acid = 118.1°C

i = Vant hoff factor = 1 (for non-electrolyte)

$K_f$ = molal boiling point elevation constant = 3.08°C/m

m = molality of solution = 0.0312 m

Putting values in above equation, we get:

$\text{Boiling point of solution}-118.1^oC=1\times 3.08^oC/m\times 0.0312m\\\\\text{Boiling point of solution}=118.2^oC$

Hence, the boiling point of solution is 118.2°C

8 0

3 years ago

Which best describes an element? A pure substance. A type of a mixture. A pure compound. An impure substance.

mr Goodwill [35]

a pure compound because an element is untouched and is just itself

7 0

3 years ago

Read 2 more answers

What is bias in an experiment?

11111nata11111 [884]

I’m not sure what the answer is but I hope someone can help you

3 0

2 years ago

Which element most likely has the same number of valence electrons as silicon(si)?

Blizzard [7]

Answer:

Carbon, germanium, tin and lead.

Explanation:

The silicon is belong to the carbon family. There are five elements in carbon family carbon, silicon, germanium, tin and lead. These five elements are present in same group i.e group fourteen. The elements present in same group have same number of valance electrons.

For example.

Carbon electronic configuration:

C₆ = [He] 2s² 2p²

Silicon electronic configuration:

Si₁₄ = [Ne] 3s² 3p²

Germanium electronic configuration:

Ge₃₂ = [Ar] 3d¹⁰ 4s² 4p²

Tin electronic configuration:

Sn₅₀ = [Kr] 4d¹⁰ 5s² 5p²

Lead electronic configuration:

Pb₈₂ = [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p²

we can see that in case of all elements there are four valance electrons, which are equal to the valance electrons of silicon.

7 0

3 years ago

The number of electrons in a neutral atom of hydrogen (H) atom is

vesna_86 [32]

There is one electron

7 0

3 years ago