The reaction times for three trials of an experiment are 80.3, 80.2, and 80.5 seconds. Which average time is expressed using the correct number of significant figures?

A. 80.3

B. 80.33

C. 80

D. 80.333

What mass of h2o will be produced if 9.5 g of h2 reacts with 1.2 g of o2?

Which elements have fewer than four dots in their electron dot diagrams? Check all that apply Arsenic (As) strontium (Sr) Krypton (Kr) Gallium (Ga) Tin (Sn) Sulfur (S)

A compound has a gram formula mass of 56 grams per mole. What is the molecular formula for this compound? (1) CH2 (3) C3H6 (2) C2H4 (4) C4H8

What is the value of x in the equation -8 = x - 15

Suggest two ways that chemical pollutants could be carried far from their sources

Which of the following statements about igneous rocks is correct A. intrusive igneous rocks are formed when magma is called above the ground. B. Extrusive igneous rocks are formed when magma is cooled above the ground C.

The compound KOH is called

A balloon contains 1.00 mol helium gas at STP. What will the volume of the balloon be if the pressure increases to 2.00 atm?

If 100 mL of a gas were enclosed in a buret at 500 mm Hg, what volume would the gas occupy at 1000 mm Hg at the same temperature? P1V1=P2V2

Would Mn (HPO4) 2 be manganese (II) monohydrogen phosphate?