The term half-life, as applied to a reactant in a chemical reaction means: the time required for half of the maximum amount of product to be formed. the time taken for the concentration of a reactant to decrease by a factor of 1/2. half of the time it ta kes for all of a reactant to be consumed. the value of time which gives a value of 1/2 when substituted into the expression kt.

An alcohol thermometer makes use of alcohol's changing in order to measure temperature. as the temperature goes up, the alcohol contained in the thermometer increases in volume, filling more of the thermometer's tube.

Agroup of students is studying convection currents. they fill two identical balloons with the same amount of helium. one balloon is placed in a freezer and the other in an area with warm air. after 10 minutes, the balloons are released from a height of 1 meter. which of the following do the students most likely observe? a. the balloons both rise. the cold balloon is larger than the warm balloon. b. the balloons rise at the same rate. both balloons are the same size. c. the warm balloon expands and rises. the cold balloon shrinks and sinks. d. the cold balloon expands and rises. the warm balloon shrinks and sinks.

If 22.5 liters of oxygen reacted with excess of hydrogen, how many liters of water vapor could be produced?