CHEMISTRY

Mixturs and solutions

100

What type of mixtures are evenly mixed?

Homogenous mixtures

200

Define soluble and insoluble

Soluble-able to dissolve in solvent

Insoluble-unable to dissolve in solvent

300

What is the formula for molarity

M=moles of solute/liters of solution

400

What happens to a solution when more solvent is added?

The solution becomes more concentrated and diluted

500

How many grams of 3.3% protein solution should be given intravenously to a patient so that he will receive 200 grams of protein

3.3%/100=0.033                

0.033=200g/litters of solution          

liters of solution=200/0.0033         

 liters of solution=6060.6L

Energy and chemical change

100

Does an endothermic reaction  absorbe or  realize energy

Endothermic reaction absorbes energy.

200

What is the chemical term for ‘’ energy can’t be created or destroyed only changed”.

Law of conservation of matter.

300

Calculate the heat required to raise 50 g of water from 20°C to 80°C.

• m=50g
• c=4.18 J/g∘Cc=4.18J/g∘C
• ΔT=80−20=60∘CΔT=80−20=60∘C

Q=50×4.18×60Q=50×4.18×60Q=12540 JQ=12540J

400

Name 2  formulas for Heating curve.

Q=mcΔTQ    Q=mH(fusion or vaporization)

500

During melting, heat is absorbed. True or false? Explain why.

True. Heat is absorbed because energy is used to break the intermolecular forces holding the solid together, allowing it to become a liquid.

Reaction rates

100

What theory explains that particles must collide to react?

Collision theory

200

Student is increasing temperature during reaction what is happening with reaction rate?

Reaction rate is increasing

300

Rate compares two quantities with different units list at least 3 of them.

miles/hour     Steps/day    $/pound

400

When activation is energy is high why is it higher for reaction to happen?

Because particles need more energy to reach the activated complex

500

Name and describe the factors affecting reaction rates.

Surface area-more area=faster reaction, 

Concentration-more particles=faster reaction, 

Temperature=higher temperature=particles move faster=faster reaction ,

Catalyst=speeds up the reaction by lowering activation energy, 

Inhibitors=slow down or blocks reaction occur

Chemical equilibrium

100

What is equilibrium in a chemical reaction?

When forward and reverse reaction rates are equal.

200

If K is very large, are products or reactants favored?

Products are favored.

300

According to Le Chatelier’s Principle, what happens if temperature increases in an endothermic reaction?

The reaction shifts toward the products.

400

Write the equilibrium expression for

N₂ + 3H₂ ⇌ 2NH₃

 Keq=[NH₃]²÷([N₂][H₂]³

500

For the reaction:
N₂(g) + 3H₂(g) ⇌ 2NH₃(g)

At equilibrium, the concentration values are:
[N₂] = 0.50 M, [H₂] = 0.30 M, [NH₃] = 0.40 M

1. Write the equilibrium expression (Keq).
2. Calculate the value of Keq
3. Is the reaction product-favored or reactant-favored?

1. Keq= [NH₃]² / ([N₂][H₂]³)
2. Substitute values:
   Keq = (0.40)² / (0.50 × (0.30)³)
   Keq = 0.16 / (0.50 × 0.027)
   Keq= 0.16 / 0.0135
   Keq=11.85
3. Since Keq > 1, the reaction is product-favored 

Acid and base

100

What ion do acids produce in water?

Hydrogen ions (H⁺).

200

What is the pH of a neutral solution?

7.

300

What happens in a neutralization reaction?

An acid reacts with a base to form water and a salt.

400

What is the conjugate base of H₂SO₄ after it donates one hydrogen ion (H⁺)?

 HSO₄⁻

500

A solution has a hydrogen ion concentration of 1 × 10⁻⁵ M. What is the pH, and is the solution acidic, basic, or neutral?

The pH is 5, so the solution is acidic.