A single atom of an element has 21 neurons 20 electrons and 20 protons which element is it?

Atoms clump together

A vector is an arrow that shows both ___ and direction Of an object in motion

What is the special compound

What is the chemical composition of bituminous coal?

A 500 mL sample of 0.5 M NaOH at 20 C is mixed with an equal volume of 0.5 M HCl at the same temperature in a calorimeter. The temperature rises to 23.21 C. Calculate the heat of the reaction. ( - 53.72 kJ/mol)

How many calories are there in a 255 Food Calorie snack bar? a. 1 x 103 b. 2.55 x 105 c. 1.07 x 103 d. 60.9 e. none of the above

What is the greatest amount of ammonia (NH3) in moles that can be made with 4.7 mol N2 and 6.9 mol H2? Which reactant is limiting? How many moles of excess reactant will be left after the reaction?

Which one of these elements is an alkaline earth metal

Write the chemical equations for the neutralization reactions that occurred when hcl and naoh were added to the buffer solution.

Explain The relationship between engineering science and technology