Which of these is a mixture? Oxygen, air, sugar or common salt

What occurs during the death of a large star to make all heavy elements?

How many liters of oxygen gas, at 285 K and 1.2 atm, will react with 35.4 grams of calcium metal? Show all of the work used to solve this problem.

What you can and what you can't do to energy?

How many neutrons does an atom of al-27 have? (hint: look at the periodic table for the atomic number aluminum (al) 13 14 27 40 aluminum has the atomic number of 13?

How many nanometers are in 4.5x10^3 cm?

The activation energy for the reaction no2 (g) + co (g) ⟶no (g) + co2 (g) is ea = 100 kj/mol and the change in enthalpy for the reaction is δh = - 375 kj/mol.

What process transform solar energy into chemical energy?

When the reaction was carried out the calculated theoretical yield for water was 176 grams but the measured yield was 148 grams what is the percent yield

For an atom's electrons, how many energy sublevels are present in the principal energy level n = 4?

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.