Which of the following is the electron configuration for an electrically neutral atom of beryllium (Be) ?

1s^2 2s^2

1s2^2s2^2p^6

1s^22s^22p^4

1s^22s^22p^44d^2

What is the meaning of Meniscus?

Which statement is true of a catalyst? A. It behaves as a reactant in a chemical reaction. B. It increases the temperature of a reaction. C. It decreases the concentration of the products. D. It accelerates the reaction rates of a mixture.

if 5.00mL of 6.00 M HCI is added to 95.00 mL of pure water, the final volume of the solution is 100.00 mL. What is the pH of the solution?

If you start with 163 g of water at 29◦C, how much heat must you add to convert all the liquid into vapor at 100◦C? Assume no heat is lost to the surroundings. Answer in units of kJ.

What makes an atom an isotope

Assuming that air contains 78 percent N2, 21 percent O2 and 1 percent Ar, all by volume. How many molecules of each type of gas are present in 1.0 L of air at STP?

Two children are playing tag. Child A who is doing the chasing can run 100m in 24 seconds Child B is running away from child A and can run 64m in 21 seconds.

What ion does a base increase

What is the definition of Amplitude?

An excess of NiCO3, 12 g, was added to 40cm cube of sulpheric acid, 2.0 mol/dm cube. The unreacted nickel carbonate was filtered out and the filtrate evaporated to optain the crystals.