How does helium form

Are plant cells affected when water is scarce

What is the net charge on an ion that has 9 protons, 11 neutrons, and 10 electrons? (1) 1 + (3) 1- (2) 2 + (4) 2-

A solution is 40.0% by volume benzene (C6H6) in carbon tetrachloride at 20C. The vapor pressure of pure benzene at this temperature is 74.61 mmHg and its density is 0.87865 g/cm3; the vapor pressure of pure carbon tetrachloride is 91.

How many moles of calcium (Ca) atoms are there in 77.4 g of Ca?

An automobile engine provides 642 Joules of work to push the pistons. In this process the internal energy changes by - 2952 Joules. Calculate q for the engine. This represents the amount of heat that must be carried away by the cooling system.

The half-life of a certain radioisotope is 8 days. How much (mass) of a 80 mg sample will remain after 24 days?

BF3 type of compound

What direction do electrons flow in an electrolytic cell? A. From cathode to anode B. From anode to cathode C. Through the salt bridge D. From electrode to electrolyte

What is the atomic nucleus made of? only neutrons electrons only protons nucleons

How many ml of 2.50 m hno3 are needed to prepare a 75.0 ml of 1.00 m hno3?