AP Chemistry Quiz 1

 $\frac{6.305\times2.90}{18.7-1.6}$  Calculate these problems and show the correct amount of significant figures.

• 12.5

• 11

• 11.4

• 12

 $\frac{\left(9.5+4.1+2.8+3.175\right)}{4}$  

• 4.7

• 5.1

• 4.9

• 4.5

For a pharmacist dispensing pills or capsules, it is often easier to weigh the medication to be dispensed than to count the individual pills. If a single antibiotic capsule weighs 650 mg and a pharmacist weighs out 15.6 g of capsules, how many capsules have been dispensed? Hint: 1 gram = 1000mg

• 24 capsules

• 23 capsules

• 34 capsules

• 14 capsules

Suppose a teaspoon of magnesium filings and a teaspoon of powdered sulfur are placed together in a metal beaker. Would this constitute a mixture or a pure substance?

• pure substance

• mixture

Chemistry majors sometimes get holes in cotton jeans they wear to lab because of acid spills. Is this a chemical or physical change?

• Physical

• Chemical

Interaction of food with saliva and digestive enzymes. Is this a chemical or physical change?

• Chemical

• Physical

How many protons does Oxygen have?

• 7

• 8

• 9

• 10

How many significant figures does 101 have?

• 2

• 3

• None of the above

How many significant figures does 400.000 have?

• 6

• 7

• None of the above

What is the formula for the compound barium fluoride?

• BaF

• BF

• BrF₂

• BaF₂