If element x has 20 protons, how many electrons does it have

At a certain temperature the vapor pressure of pure heptane C7H16 is measured to be 454. mmHg. Suppose a solution is prepared by mixing 102. g of heptane and 135. g of chloroform CHCl3.

Iodine has many isotopes, but only iodine-127 is stable and is found in nature. One radioactive iodine isotope, I-108, decays by alpha particle emission. Iodine-131 is also radioactive and has many important medical uses.

What combines genetic material from two different parent cells

The decomposition of dinitrogen pentaoxide has an activation energy of 102 kj/mol and / delta? h°rxn = + 55 kj/mol. what is the activation energy for the reverse reaction?

A 211 g sample of barium carbonate, baco3, reacts with a solution of nitric acid to give barium nitrate, carbon dioxide, and water. if the acid is present in excess, what mass and volume of dry carbon dioxide gas at stp will be produced?

Which ionic compound is water soluble? A. cuS B. NH4NO3 C. SrSO4 D. ZnF

What is part of an experiment that is not being tested and is used for comparison

Is hydrogen sulfide a heterogeneous mixture solution compound or element?

Explain why people who like to stay cool on a hot summer day prefer to wear white clothing?

Which of these is a chemical property? A. Mercury is a dense liquid. B. Iodine vapor has a purple color. C. Aluminum is a very conductive metal. D. Ice melts at 0°C. E. Iron rusts in wet weather.