What tells the number of protons in the nucleus of every atom of an element

Complete combustion of 2.90g of a hydrocarbon produced 9.32g of CO2 and 3.18g of H2O. What is the empirical formula for the hydrocarbon?

Calculate the number of mol corresponding to 2.20 g Cl2. Enter your answer in the provided box. mol Cl2

Calculate the equilibrium concentration of [N2][N2] if the initial concentrations are 2.25 MM N2N2 and 0.55 MM O2O2. (This N2/O2N2/O2 concentration ratio is the ratio found in air.)

What is the smallest particle of an element that's till retains all the properties of the element?

What is the pressure exerted by 1.2 moles of a gas with a temperature of 20.0° C and a volume of 9.5 L? (R=0.0821, K=°C + 273) а 3.0 atm b 1.0 atm С 30 atm d 0.030 atm

Why does the body of the bird covered with feathers?

One molecule of caffeine contains 8 atoms of carbon, 10 atoms of hydrogen, 2 atoms of oxygen, 4 atoms of nitrogen. write the formula for caffeine with the elements in the order they are given.

A piece of magnesium metal is heated in the presence of chlorine gas, and a reaction takes place. What compound will most likely be produced? A. Mg2C1 B. MgCl3 C. MgCl2 D. MgCI

What is the pressure of the gas in this mercury manometer if h = 81 mm and atmospheric pressure is 749 mmHg

A microscope containing two or more lenses is an