Q: A sample has a mass of $$3.231\ \mu g$$ and a density of $$1.92413\ g/mL. $$What is its volume in $$mL$$?

$$1.679 \times 10$$^{-6}$$\ mL$$

Q: If you have $$9.61\ g of$$ $$(NH_4$)_3PO_4$$, how many atoms of oxygen are present in the sample? (Molar mass of $$(NH_4$)_3PO_4 = 149\ g/mol)$$

$$1.56 \times 10$$^{22}$$ atoms

Q: Convert $$3.514\ lb to$$ $$fg ($$femtograms). ($$1\ lb = 453.592\ g)$$

$$1.594 \times 10$$^{21}$$\ fg$$

Q: How many $$O$$ atoms are in $$3.113 \times 10$$^{14}$$ molecules of N_2O_5$?

$$1.56 \times 10$$^{15}$$ atoms

Q: A sample contains $$3.914 \times 10$$^{15}$$ molecules of NH_3$. What is its mass in pg$ (picograms)? (Molar mass of NH_3$ = 17.03\ g/mol)$$

$$1.11 \times 10$$^{-7}$$\ g = 1.11 \times 10$$^{5}$$\ pg$$

Question 1

Which of the following best describes an isotope?

Accepted Answer

Atoms of the same element with different numbers of neutrons.

Question 2

A sample has a mass of $$3.231\ \mu g$$ and a density of $$1.92413\ g/mL. $$What is its volume in $$mL$$?

Accepted Answer

$$1.679 	imes 10$$^{-6}$$\ mL$$

Question 3

Which of the following is a correct net ionic equation for the reaction between ammonium nitrate and potassium chloride in aqueous solution?

Accepted Answer

No net ionic equation; all species are spectator ions.

Question 4

If you have $$9.61\ g of$$ $$(NH_4$)_3PO_4$$, how many atoms of oxygen are present in the sample? (Molar mass of $$(NH_4$)_3PO_4 = 149\ g/mol)$$

Accepted Answer

$$1.56 	imes 10$$^{22}$$ atoms

Question 5

A compound contains $$2.52\ g of $$nitrogen and $$5.47\ g of $$oxygen. What is the percent composition by mass of nitrogen in the compound?

Accepted Answer

$$46.1\%$$

Question 6

Which of the following is the correct empirical formula for a salt containing $$56.58\%$$ potassium (K), $$8.68\%$$ carbon (C), and $$34.73\%$$ oxygen (O)?

Accepted Answer

$$K_2CO_3$$

Question 7

Convert $$3.514\ lb to$$ $$fg ($$femtograms). ($$1\ lb = 453.592\ g)$$

Accepted Answer

$$1.594 	imes 10$$^{21}$$\ fg$$

Question 8

Which of the following best describes sugar (sucrose)?

Accepted Answer

A pure substance, specifically a compound

Question 9

Which of the following is NOT a diatomic element in its natural state?

Accepted Answer

Phosphorus

Question 10

If $$0.321\ g of $$methane ($$CH_4) $$reacts with $$2.981\ g of$$ $$O_2$$, what is the limiting reactant? (Molar masses: $$CH_4 = 16.04$$\ g/mol$$, O_2$ = 32.00\ g/mol)$$

Accepted Answer

$$CH_4$$

Question 11

Which of the following ionic compounds is insoluble in water?

Accepted Answer

$$FeCO_3$$

Question 12

What is the correct name for $$Fe(PO_2$)_2$$?

Accepted Answer

Iron(II) hypophosphite

Question 13

How many $$O$$ atoms are in $$3.113 	imes 10$$^{14}$$ molecules of N_2O_5$?

Accepted Answer

$$1.56 	imes 10$$^{15}$$ atoms

Question 14

Which of the following is the correct molecular formula for ammonium hypobromite?

Accepted Answer

$$NH_4BrO$$

Question 15

Convert $$4.19 	imes 10$$^{-14}$$\ kg to$$ $$ng ($$nanograms).

Accepted Answer

Question 16

Which of the following is the correct net ionic equation for the reaction of silver nitrate with iron(III) bromide?

Accepted Answer

$$3Ag^+ (aq) + $$FeBr_3$$ (aq) \rightarrow 3AgBr (s) + Fe$$^{3+}$$ (aq)$$

Question 17

A sample contains $$3.914 	imes 10$$^{15}$$ molecules of NH_3$. What is its mass in pg$ (picograms)? (Molar mass of NH_3$ = 17.03\ g/mol)$$

Accepted Answer

$$1.11 	imes 10$$^{-7}$$\ g = 1.11 	imes 10$$^{5}$$\ pg$$

Question 18

Which of the following is the correct chemical formula for iron(II) nitride?

Accepted Answer

General Chemistry: Fundamental Concepts, Calculations, and Nomenclature

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드