When did homo spiens leave africa

If a mixture of gases contained 78% nitrogen at a pressure of and 22% carbon dioxide at, what is the total pressure of the system? 1,329 atm 17.5 cm hg 639 torr 1.75 atm none of these

What volume does 14 mol of gas occupy at STP? Round to the nearest hundredth.

MgO + 2 LiCl → MgCl2 + Li2O Are all the elements balanced?

A sample of hydrated calcium sulfate has a mass of 20.88 g. After it is heated, it has a mass of 16.51 g. What is the percentage by mass of water in the hydrate

A bicyclist accelerates at 0.89m/s^2 during a 5.0 interval. What. is the change in the speed of the bicyclist and the bicycle

How many grams of tin are found in 3.5 moles of tin

Determine whether each statement is a description of a physical property or a chemical property. Paper burns readily in air.

Cual es la función de los lípidos?

Butane - ethane - methane - propane: What do these hydrocarbons have in common? A) The same number of carbons present. B) They all have polar covalent bonds. C) They all have single covalent bonds. D) They have the same structural formulas.

Identify the form of energy that is converted into ther - mal energy by your body