What is a controlled experiment? a. one variable is changed at a time b. none of the variables are changed c. all variables are kept constant d. two variables are changed at a time

Use the gizmo to find the concentration of the mystery ch3cooh. use the titrant and indicator shown below perform the titration. what is the titrant volume? titrant analyte indicator titrant volume analyte concentration naoh ch3cooh phenophthalein select one: a. 20.0 ml b. 27.0 ml c. 30.0 ml d. 24.0 ml

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

Calculate the estimated density of each ball. use the formula d = m/v where d is the density, m is the mass, and v is the volume. record your calculations in table a of your student guide. given that the density of water is 1.0 g/cm3, make a prediction about whether each ball will float in water. record your prediction in table a. what is the estimated density of the table tennis ball? record your answer to the nearest hundredth