The pressure of a sample of gas of constant volume is 2.0 atm at 30.ºC. What is the pressure of this sample at 20.ºC?

The value of keq for the equilibrium n2 (g) o2 (g) 2 no (g) is 4.2 x⋅10-31 at 27 °c. what is the value of keq for the equilibrium below

If a substance changes from one phase to another, is it still same substance? why

Electric fields can be seen by human eyes. O A. True O B. False

Cobalt-63 has a half-life of 5.3 years. If a pellet that has been in storage for 15.9 years contains 40.0g of Cobalt-63, how much of this radioisotope was present when the pellet was put into storage? Show work.

2. Where are valence electrons located?

Attempt 2 A sample of gas contains 49.16 % N 2 gas, 19.85 % Br 2 gas, 9.95 % CO 2 gas, and 21.04 % of an unknown gas. The average atomic mass of the gas mixture is 50.71 u. Calculate the atomic mass of the unknown gas.

A chemist determined by measurements that. 040 moles of gold participated in a chemical reaction. calculate the mass of gold that participated in the chemical reaction. round your answer to significant digits.

10) A screwdriver has the density of 5.5 grams per cubic centimeter. It also has the mass of 2.3 grams. What is the screwdriver's volume?

A chemist weighed out 20.7 g of sodium. Calculate the number of moles of sodium she weighed out

If 1.00 mol of argon is placed in a 0.500-L container at 20.0 ∘C, what is the difference between the ideal pressure (as predicted by the ideal gas law) and the real pressure (as predicted by the van der Waals equation) ? For argon, a=1.