What is the total number of valence electrons in a calcium atom in the ground state?

(1) 8 (3) 18

(2) 2 (4) 20

A balloon filled with gas expands in volume by 2.0 L against an external pressure of 0.93 atm. If the balloon has absorbed 636 J of heat from the surroundings, what is the change in the balloon's internal energy? (note: 1 L-atm = 101.3 J)

How many grams of potassium nitrate can dissolve in 100g of water at 50C?

How is mechanical energy related to potential energy and to kinetic energy

How many moles of S2F10 are contained in a pure 128-gram sample of S2F10?

The greatest amount of energy released per gram of reactants occurs during a (1) redox reaction (2) fission reaction (3) substitution reaction (4) neutralization reaction

Which of the following statements about the suns feature is true?

Preteins vary widely in structure, whereas nucleic acids have rather uniform structures. How do you account for this major difference?

Convert the pressure 0.840 atm to mm Hg

What is the temperature in Celsius of 308 K?

Why does metal need to be extracted from an ore before it can be used?