Q: Which of the following gives the balanced equation for the reaction: K$$_3PO$_4 + Ca(NO$_3$$)$$_2$$ → Ca$$_3(PO$_4$$)$$_2 + $$KNO$$_3$$?

$$2\ \text{K}_3\text{PO}_4 + 3\ \text{Ca(NO}_3)_2 \rightarrow \text{Ca}_3(\text{PO}_4)_2 + 6\ \text{KNO}_3$$

Q: Which of the following is a balanced equation for the combustion of methane?

$$\text{CH}_4 + 2\ \text{O}_2 \rightarrow \text{CO}_2 + 2\ \text{H}_2\text{O}$$

Question 1

Calculate the molar mass of magnesium chloride, MgCl$$_2.$$

Accepted Answer

$$76.33\ 	ext{g/mol}$$

Question 2

What is the molar mass, to three significant figures, of calcium phosphate, Ca$$_3(PO$_4$$)$$_2$$?

Accepted Answer

$$263\ 	ext{g/mol}$$

Question 3

What is the mass percent of carbon in methane, CH$$_4$$?

Accepted Answer

$$75.0\%$$

Question 4

Calculate the empirical formula of a compound that has a composition of $$5.9\%$$ hydrogen and $$94.1\%$$ oxygen.

Accepted Answer

H$$_2O$$

Question 5

What is the mass of the compound between calcium and sulfate that has the percent composition $$29.4\%$$ calcium and $$70.6\%$$ sulfate?

Accepted Answer

$$136\ 	ext{g/mol}$$

Question 6

Which of the following gives the balanced equation for the reaction: K$$_3PO$_4 + Ca(NO$_3$$)$$_2$$ → Ca$$_3(PO$_4$$)$$_2 + $$KNO$$_3$$?

Accepted Answer

$$2\ 	ext{K}_3	ext{PO}_4 + 3\ 	ext{Ca(NO}_3)_2 ightarrow 	ext{Ca}_3(	ext{PO}_4)_2 + 6\ 	ext{KNO}_3$$

Question 7

What coefficient is placed in front of O$$_2 to $$complete the balancing of the following equation?

C$$_2H$_4 (g) + O$_2 (g$$) → CO$$_2 (g) + H$_2O (g)$$

Accepted Answer

$$3$$

Question 8

What is the coefficient of hydrogen, H$$_2$$, when the following equation is balanced?

Al (s) + H$$_2SO$_4 (aq$$) → Al$$_2(SO$_4$$)$$_3 (aq) + H$_2 (g)$$

Accepted Answer

$$3$$

Question 9

Pentane (C$$_5H$_{12}) $$reacts with oxygen (O$$_2) to $$form carbon dioxide (CO$$_2) $$and water (H$$_2O) $$according to the following reaction. What is the coefficient for oxygen in the balanced equation?

Accepted Answer

$$8$$

Question 10

A patient receives a saline solution containing NaCl. If the solution contains $$0.9\%$$ NaCl by mass and the patient receives $$500\ 	ext{mL}$$, how many grams of NaCl did the patient receive? (Assume density of solution is $$1.0\ 	ext{g/mL})$$

Accepted Answer

$$4.5\ 	ext{g}$$

Question 11

Which of the following compounds is ionic?

Accepted Answer

NaCl

Question 12

Which of the following is a correct molecular formula for a compound with $$40.0\%$$ carbon, $$6.7\%$$ hydrogen, and $$53.3\%$$ oxygen?

Accepted Answer

C$$_2H$_6O$$

Question 13

Which of the following is the correct formula for calcium nitrate?

Accepted Answer

Ca(NO$$_3$$)$$_2$$

Question 14

A sample contains $$0.5\ 	ext{mol} of $$water. How many molecules are present?

Accepted Answer

$$3.01 	imes 10$$^{23}$$

Question 15

Which of the following is a balanced equation for the combustion of methane?

Accepted Answer

$$	ext{CH}_4 + 2\ 	ext{O}_2 ightarrow 	ext{CO}_2 + 2\ 	ext{H}_2	ext{O}$$

Question 16

Which of the following is the correct formula for aluminum sulfate?

Accepted Answer

Al$$_2(SO$_4$$)$$_3$$

Question 17

A $$10.0\ 	ext{g}$$ sample of glucose (C$$_6H$_{12}O$_6) is $$dissolved in $$100.0\ 	ext{g} of $$water. What is the mass percent of glucose in the solution?

Accepted Answer

$$9.09\%$$

Question 18

Which of the following is a correct empirical formula for a compound with $$60.0\%$$ magnesium and $$40.0\%$$ oxygen?

Accepted Answer

MgO

Question 19

Which of the following is the correct formula for potassium phosphate?

Accepted Answer

K$$_3PO$_4$$

CHEM-1050 Test 3 Study Guidance: Chapters 7, 8, and 9

Study Guide - Practice Questions

Study Guide - Flashcards