Question 1 (4 points) (01.05 MC)
During an experiment a thermometer was placed in a beaker containing hydrogen peroxide. The following observations were recorded when
yeast granules were added to hydrogen peroxide.
Observation 1: Fizzing and bubbling took place.
Observation 2: The temperature began to rise.
Based on the observation, justify the type of change (physical or chemical) that took place. (4 points)

Hot air balloons float in the air because of the difference in density between cold and hot air. in this problem, you will estimate the minimum temperature the gas inside the balloon needs to be, for it to take off. to do this, use the following variables and make these assumptions: the combined weight of the pilot basket together with that of the balloon fabric and other equipment is w. the volume of the hot air inside the balloon when it is inflated is v. the absolute temperature of the hot air at the bottom of the balloon is th (where th> tc). the absolute temperature of the cold air outside the balloon is tc and its density is ďc. the balloon is open at the bottom, so that the pressure inside and outside the balloon is the same. as always, treat air as an ideal gas. use g for the magnitude of the acceleration due to gravity.

What is the molar mass of ca(cio4)2

He table below gives the atomic mass and relative abundance values for the three isotopes of element m. relative abundance (%) atomic mass (amu) 78.99 23.9850 10.00 24.9858 11.01 25.9826 what is the average atomic mass (in amu) of element m? 2.86 5.36 24.30 24.98