Q: Which of the following statements about Avogadro’s number is correct?

It is the number of particles in one mole, $$6.02 \times 10$$^{23}$$.

Question 1

Which of the following best describes a chemical reaction?

Accepted Answer

A process where atoms are rearranged and new substances are formed.

Question 2

Which indicator would most likely suggest a chemical reaction has occurred in nature?

Accepted Answer

A color change in leaves during autumn.

Question 3

What is the correct balanced equation for the reaction: Fe(s) + CO2(g) → Fe2O3(s) + CO(g)?

Accepted Answer

$$4Fe(s) + 3CO_2(g) \rightarrow 2Fe_2O_3(s) + 3CO(g)$$

Question 4

Which type of reaction is represented by: 2H2O2(l) → 2H2O(l) + O2(g)?

Accepted Answer

Decomposition

Question 5

A reaction where two compounds exchange elements to form two new compounds is called:

Accepted Answer

Double replacement reaction

Question 6

Which equation represents a combustion reaction?

Accepted Answer

$$CH_4(g) + 2O_2(g$$) \rightarrow $$CO_2(g) + 2H_2O(g$$)$$

Question 7

In the reaction: Fe(s) + 2AgNO3(aq) → Fe(NO3)2(aq) + 2Ag(s), which species is oxidized?

Accepted Answer

Fe(s)

Question 8

Which memory trick helps students remember the definitions of oxidation and reduction?

Accepted Answer

LEO the Lion Says GER

Question 9

How many molecules are in 5 moles of water?

Accepted Answer

$$3.01 	imes 10$$^{24}$$

Question 10

What is the molar mass of glucose ($$C_6H_{12}O_6$)?

Accepted Answer

$$180.16\ g/mol$$

Question 11

A sample contains 3.45 g of glucose ($$C_6H_{12}O_6$). How many moles of glucose are present?

Accepted Answer

$$0.0192\ mol$$

Question 12

Which of the following is NOT a correct indicator of a chemical reaction?

Accepted Answer

A change in physical state without new substances forming.

Question 13

Which of the following statements about Avogadro’s number is correct?

Accepted Answer

It is the number of particles in one mole, $$6.02 	imes 10$$^{23}$$.

Question 14

Which reaction is an example of a single replacement reaction?

Accepted Answer

$$Zn(s) + 2HCl(aq) \rightarrow $$ZnCl_2$$(aq) + H_2$(g)$$

Question 15

In biological systems, oxidation can involve:

Accepted Answer

Addition of oxygen or loss of hydrogen.

Question 16

What is the theoretical yield?

Accepted Answer

The maximum calculated mass of product from a given mass of reactant.

Question 17

Which conversion factor would you use to convert grams of NaCl to moles of NaCl?

Accepted Answer

$$\frac{1\ mol\ NaCl}{58.44\ g\ NaCl}$$

Question 18

A hydrocarbon burns in oxygen to produce carbon dioxide and water. What type of reaction is this?

Accepted Answer

Combustion

Question 19

Which of the following is a correct mole ratio for the reaction: $$N_2(g$$) + $$O_2(g$$) \rightarrow 2NO(g)$$?

Accepted Answer

$$1\ mol\ N_2$ : 2\ mol\ NO$$

Question 20

If you have $$3.64 × 10^7 g of (NH4)2SO4$$, how many grams of NH3 are needed? (Given: $$H_2SO_4(aq) + 2NH_3(g) \rightarrow (NH_4$)_2SO_4(aq)$$; molar masses: $$H_2SO_4 = 98.08\ g/mol$$, $$NH_3 = 17.03$$\ g/mol$$, $$($$NH_4)_2SO_4 = 132.14$$\ g/mol$$)

Accepted Answer

$$9.38 	imes 10^6$\ g$$

Chapter 8: Chemical Reactions – Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard