Chemical Reactions Pre-assessment

1. Chemical reactions

Occur only in living organisms.

Create and destroy atoms.

Only occur outside living organisms.

Produce new substances.

2. In a combustion reaction, one of the reactants is

Hydrogen

Nitrogen

Oxygen

Metal

3. What does the triangle symbol above the arrow in a chemical equation mean?

Heat is supplied to the reaction.

A catalyst is needed in the reaction.

Electricity is need in the reaction.

A precipitate will form during the reaction.

4. When the following equation is balanced, what is the coefficient for HCl? Mg(s) + HCl (aq) à MgCl₂(aq) + H₂ (g)

6

3

1

2

5. The equation H3PO4 + 3KOH --> K3PO3 + 3H2O is an example of which type of reaction?

Double-replacement reaction

Combination reaction

Decomposition reaction

Single-replacement reaction

6. The reaction 2Fe + 3Cl2 --> 2FeCl3 is an example of which type of reaction?

Combustion reaction

Single-replacement reaction

Combination reaction

Decomposition reaction

7. Which of the following statements is true about what happens in all chemical reactions?

The ways in which atoms are joined together is not changed.

New atoms are formed as products.

The final substances are called reactants.

Bonds between atoms are broken and new bonds are formed.

8. Which of the following combinations of symbol and explanation of symbol is correct when used in a chemical equation?

(g), grams

(l), liters

(aq), dissolved in water

(s), solid product

9. In the chemical equation H2O2 à H2O + O2f the O2 is a ____.

Catalyst

Solid

Product

Reactant

10. Which of the following is the correct skeleton equation for the reaction that takes place when solid phosphorus combines with oxygen gas to form diphosphorus pentoxide?

P (s) + O2(g) -->P O2 (g)

P(s) + O2(g) --> P5 O2 (g)

P(s) + O2(g) -->P2 O5 (s)

P2 O5 (s) --> P2 (s) + O2 (g)

11. The equation Mg(s) + 2HCl(aq) --> MgCl2(aq) + H2(g) is an example of which type of reaction?

Combination reaction

Single-replacement reaction

Decomposition reaction

Double-replacement reaction

12. A net ionic equation

Shows the spectator ions.

Shows only those particles involved in the reaction.

Is not necessarily balanced with respect to mass or charge.

Shows dissolved ionic compounds as dissociated free ions.

13. When the equation Fe + Cl₂ à FeCl₃ is balanced, what is the coefficient for Cl?

1

2

3

4

14. When the equation KClO₃ (s) à KCl (s) + O₂ (g) is balanced, the coefficient of KClO₃ is

1

2

3

4

Chemical Reactions Pre-assessment

1. Chemical reactions

2.

What first name or nickname would you like us to use?

2. In a combustion reaction, one of the reactants is

3. What does the triangle symbol above the arrow in a chemical equation mean?

4. When the following equation is balanced, what is the coefficient for HCl? Mg(s) + HCl (aq) à MgCl₂(aq) + H₂ (g)

5. The equation H3PO4 + 3KOH --> K3PO3 + 3H2O is an example of which type of reaction?

6. The reaction 2Fe + 3Cl2 --> 2FeCl3 is an example of which type of reaction?

7. Which of the following statements is true about what happens in all chemical reactions?

8. Which of the following combinations of symbol and explanation of symbol is correct when used in a chemical equation?

9. In the chemical equation H<sub>2</sub>O<sub>2</sub> à H<sub>2</sub>O + O<sub>2</sub>f the O<sub>2</sub> is a ____.

10. Which of the following is the correct skeleton equation for the reaction that takes place when solid phosphorus combines with oxygen gas to form diphosphorus pentoxide?

11. The equation Mg(s) + 2HCl(aq) --> MgCl2(aq) + H2(g) is an example of which type of reaction?

12. A net ionic equation

13. When the equation Fe + Cl₂ à FeCl₃ is balanced, what is the coefficient for Cl?

14. When the equation KClO₃ (s) à KCl (s) + O₂ (g) is balanced, the coefficient of KClO₃ is

Chemical Reactions Pre-assessment

1. Chemical reactions

2.

What first name or nickname would you like us to use?

2. In a combustion reaction, one of the reactants is

3. What does the triangle symbol above the arrow in a chemical equation mean?

4. When the following equation is balanced, what is the coefficient for HCl? Mg(s) + HCl (aq) à MgCl2 (aq) + H2 (g)

5. The equation H3PO4 + 3KOH --> K3PO3 + 3H2O is an example of which type of reaction?

6. The reaction 2Fe + 3Cl2 --> 2FeCl3 is an example of which type of reaction?

7. Which of the following statements is true about what happens in all chemical reactions?

8. Which of the following combinations of symbol and explanation of symbol is correct when used in a chemical equation?

9. In the chemical equation H<sub>2</sub>O<sub>2</sub> à H<sub>2</sub>O + O<sub>2</sub>f the O<sub>2</sub> is a ____.

10. Which of the following is the correct skeleton equation for the reaction that takes place when solid phosphorus combines with oxygen gas to form diphosphorus pentoxide?

11. The equation Mg(s) + 2HCl(aq) --> MgCl2(aq) + H2(g) is an example of which type of reaction?

12. A net ionic equation

13. When the equation Fe + Cl2 à FeCl3 is balanced, what is the coefficient for Cl ?

14. When the equation KClO3 (s) à KCl (s) + O2 (g) is balanced, the coefficient of KClO3 is

4. When the following equation is balanced, what is the coefficient for HCl? Mg(s) + HCl (aq) à MgCl₂(aq) + H₂ (g)

13. When the equation Fe + Cl₂ à FeCl₃ is balanced, what is the coefficient for Cl?

14. When the equation KClO₃ (s) à KCl (s) + O₂ (g) is balanced, the coefficient of KClO₃ is