A large weather balloon filled with helium has a volume of 7.00 x 102 L at STP. Which expression should be used to find the mass of helium in the balloon?

List the gases h2o, he, hcl, brf, and no2 in order of increasing average molecular velocity at 25◦c. 1. rates of effusion: no2 < hcl < brf < he < h2o 2. rates of effusion: brf < no2 < hcl < h2o < he 3. rates of effusion: h2o < no2 < he < brf < hcl 4.

Which of the following lists only include molecules? He h2o

What is the concentration (in %v/v)) of the following solutions? a. 25 mL of ethanol is diluted to a volume of 150 mL with water.

How many moles of MgCl2 are there in 335 g of the compound?

A 100.0 g sample of water at 27.0°c is poured into a 70.3 g sample of water at 89.0°c. what will be the final temperature of the water?

The energy of a particular color of green light is 3.81*10-22 kJ/photon. The wavelength of this light is nanometers

How many molecules are in. 25 mole of O2

A flexible container is filled with 960.0 liters of air at 38 degrees Celsius. If pressure in the container does not change, at what temperature will the container have at a volume of 350.0 liters?

Which subatomic particles are paired with their charges? 1. electron-positive, neutron-negative, proton-neutral 2. electron-negative, neutron-neutral, proton-positive 3. electron-negative, neutron-positive, proton-neutral 4.

Where do you think information is coded in a DNA molecule?