Q: What is the percent by mass of solute in a solution made by dissolving 5 grams of NaCl in 95 grams of water?

$$\frac{5}{100} \times 100\% = 5\%$$

Q: A solution is made by adding 20 grams of NaCl to 80 grams of water. What is the percent by mass of NaCl in the solution?

$$\frac{20}{100} \times 100\% = 20\%$$

Q: If 0.013 grams of manganese are found in 1000 grams of water, what is the concentration of manganese in ppm?

$$\frac{0.013}{1000} \times 10^6$ = 13$$ ppm

Question 1

Which of the following best describes an ionic compound?

Accepted Answer

A compound consisting of a metal and a nonmetal, held together by electrostatic attraction between oppositely charged ions.

Question 2

Which of the following is the correct formula for magnesium chloride?

Accepted Answer

$$\mathrm{$$MgCl_2$$}$$

Question 3

A student dissolves 10 grams of KNO$$_3 in 100 $$grams of water at 40$$^\circC. $$According to the solubility graph, is this solution saturated, unsaturated, or supersaturated?

Accepted Answer

Unsaturated, because the amount of KNO$$_3 is $$less than the solubility at 40$$^\circC.$$

Question 4

Which of the following statements about covalent compounds is TRUE?

Accepted Answer

They are formed by the sharing of electrons between nonmetal atoms.

Question 5

What is the percent by mass of solute in a solution made by dissolving 5 grams of NaCl in 95 grams of water?

Accepted Answer

$$\frac{5}{100} 	imes 100\% = 5\%$$

Question 6

Which of the following best explains why ionic compounds conduct electricity when dissolved in water?

Accepted Answer

The ions are free to move and carry electric current.

Question 7

Which element is always listed first in the formula of an ionic compound?

Accepted Answer

The metal element.

Question 8

A solution is made by adding 20 grams of NaCl to 80 grams of water. What is the percent by mass of NaCl in the solution?

Accepted Answer

$$\frac{20}{100} 	imes 100\% = 20\%$$

Question 9

Which of the following compounds is most likely to be soluble in water?

Accepted Answer

NaCl (sodium chloride)

Question 10

Which of the following best describes a solution with a high concentration?

Accepted Answer

A solution with a large amount of solute relative to solvent.

Question 11

Which of the following is a chemical change?

Accepted Answer

Burning magnesium ribbon.

Question 12

What type of bond is formed when electrons are transferred from one atom to another?

Accepted Answer

Ionic bond

Question 13

Which of the following best describes the difference between a compound and a mixture?

Accepted Answer

A compound is made of two or more elements chemically combined, while a mixture is made of substances physically combined.

Question 14

If 0.013 grams of manganese are found in 1000 grams of water, what is the concentration of manganese in ppm?

Accepted Answer

$$\frac{0.013}{1000} 	imes 10^6$ = 13$$ ppm

Question 15

Which of the following is NOT a property of ionic compounds?

Accepted Answer

Formed by sharing electrons

Question 16

Which of the following best describes a saturated solution?

Accepted Answer

A solution that contains the maximum amount of solute that can dissolve at a given temperature.

Question 17

Which of the following would increase the concentration of a salt in a water solution?

Accepted Answer

Evaporating some of the water from the solution.

Question 18

Which of the following best describes the process of dissolving NaCl in water?

Accepted Answer

The Na$$^+$$ and Cl$$^-$$ ions are surrounded by water molecules and separated from each other.

Question 19

Which of the following is the correct order for classifying types of matter from MOST to LEAST complex?

Accepted Answer

Elements, atoms, compounds

Ionic vs. Covalent Compounds and Solubility: Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard