Q: How many chloride ions are present in $$4.50$$ mol of aluminum chloride ($$\mathrm{$$AlCl_3$$}$$)?

$$8.13 \times 10$$^{24}$$ chloride ions

Question 1

Which of the following best describes why NaBr is classified as an ionic compound, while CO2 is not?

Accepted Answer

NaBr contains a metal and a nonmetal, resulting in electron transfer and ionic bonding, while CO2 contains only nonmetals and forms covalent bonds.

Question 2

A sample of 10.0 g of five different elements is compared. Which element will have the fewest atoms in the sample, and why?

Accepted Answer

Cesium, because it has the largest molar mass, resulting in fewer moles and thus fewer atoms for the same mass.

Question 3

Which of the following is a correct application of significant figures when multiplying 9.040 by 0.0400?

Accepted Answer

The answer should have three significant figures, because both numbers have three significant figures.

Question 4

A 43.6 g piece of metal has a density of $$2.71\ \mathrm{g/cm^3$}. $$What is its volume in $$\mathrm{cm^3$}$$?

Accepted Answer

$$16.1\ \mathrm{cm^3$}$$

Question 5

Which of the following is an example of a chemical change?

Accepted Answer

A candle burns, producing new substances.

Question 6

How many moles are in $$2.16 	imes 10$$^{24}$$ atoms of silver ($$\mathrm{Ag}$$)? Use 6.022$$ 	imes $$10^{23}$$ for Avogadro's number.

Accepted Answer

$$3.59$$ moles

Question 7

Which of the following sets contains species with the same number of electrons?

Accepted Answer

$$\mathrm{F^-}$$, $$\mathrm{Ne}$$, $$\mathrm{Mg$$^{2+}$$}$$

Question 8

A room measures $$11.0\ \mathrm{ft} 	imes 11.0\ \mathrm{ft}$$ with a $$10.0\ \mathrm{ft}$$ ceiling. If the density of air is $$1.19\ \mathrm{g/L}$$, what is the mass of air in the room in kilograms? ($$1\ \mathrm{in} = 2.54\ \mathrm{cm}$$, $$1\ \mathrm{L} = 10^3$\ \mathrm{cm^3$})$$

Accepted Answer

$$40.8\ \mathrm{kg}$$

Question 9

Which of the following is the correct empirical formula for a compound that is $$62.0\% C$$, $$10.4\% H$$, and $$27.5\% O by $$mass?

Accepted Answer

$$\mathrm{C_3H_6O}$$

Question 10

A sample of $$3.00\ \mathrm{g} of $$ethanol ($$\mathrm{CH_3CH_2OH}) $$contains how many moles? (Molar mass $$= 46.07\ \mathrm{g/mol})$$

Accepted Answer

$$0.0652$$ mol

Question 11

Which of the following is the correct name for $$\mathrm{Ba(NO_2$)_2}$$?

Accepted Answer

Barium nitrite

Question 12

What is the correct chemical formula for the compound formed between potassium and sulfur?

Accepted Answer

$$\mathrm{K_2S}$$

Question 13

A patient is prescribed $$300\ \mathrm{mg} of a $$drug. If the drug is supplied as $$50.0\ \mathrm{mg/mL}$$, how many milliliters should be administered?

Accepted Answer

$$6.00\ \mathrm{mL}$$

Question 14

Which of the following is NOT an empirical formula?

Accepted Answer

$$\mathrm{C_2H_4O_2}$$

Question 15

Combustion analysis of a hydrocarbon yields $$0.2845\ \mathrm{g} of$$ $$\mathrm{CO_2$}$$ and $$0.1451\ \mathrm{g} of$$ $$\mathrm{H_2O}. $$What is the empirical formula of the compound?

Accepted Answer

$$\mathrm{C_2H_5}$$

Question 16

Which of the following is the correct formula for nitrous acid?

Accepted Answer

$$\mathrm{$$HNO_2$$(aq)}$$

Question 17

A person weighs $$77.1\ \mathrm{kg}. $$What is his weight in pounds? ($$1\ \mathrm{kg} = 2.20462\ \mathrm{lb})$$

Accepted Answer

$$170$$ pounds

Question 18

Which of the following is a polyatomic molecule?

Accepted Answer

Phosphorus ($$\mathrm{P_4$})$$

Question 19

How many chloride ions are present in $$4.50$$ mol of aluminum chloride ($$\mathrm{$$AlCl_3$$}$$)?

Accepted Answer

$$8.13 	imes 10$$^{24}$$ chloride ions

General Chemistry Practice Exam 1 – Guided Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard