87 g of butane (C4H10) are burnt with oxygen. a) Write the balanced chemical equation.
b) Calculate the volume of CO2 in standard condition (STP) obtained. c) Calculate the number of molecules of carbon dioxide formed.

What is the result of multiplying (2.5 × 1010) × (2.0 × 10-7)? a. 5.0 × 103 b. 5.0 × 10-3 c. 5.0 × 1017 d. 5.0 × 10-17

Maria wants to determine which type of disinfectant kills the most bacteria. which of the following is the best way for maria to determine this? a. ask ten different companies that make disinfectants which type is best. b. put the same amount and species of bacteria on ten identical plates, and add ten different kinds of disinfectant to each plate. c. interview ten different people to determine which type of disinfectant they prefer. d. put the same amount and species of bacteria on ten identical plates, and add a different disinfectant to each plate.

When an object falls through the air and encounters air resistance its overall speed will be than if it had not encountered air resistance? (one word answer)