What are the 4 quantum numbers for strontium?

Answer 1

1.) a.) Because of shielding, there are only 7 of the 17 protons of the Cl nucleus to hold the 3s2 3p5 electrons of Cl. With the gain of an electron, those 7 protons have to hold on to 8 electrons. The attraction is weaker, so Cl- is larger. In K+, there is one less electron, the 4s is empty, so K+ is smaller.

b.) Li is 1s2 2s1. The energy to remove the 2s1 is low, but the energy to remove the second electron from a filled shell is very high. Be is 1s2 2s2. The 1s2 is a filled shell, but the 2s2 is not. The energy to remove the first electron is low. The energy to remove the second is higher but not extremely high.

2.) a.) This is beyond me.

b.) Blue light is shorter in wavelength and higher in frequency than red light, so red light is less energetic.

3.) a.) All the same. "Equal volumes of gas contain equal numbers of molecules." --Avogadro.

b.) Molecular weights: NH3=17, NO2=46, N2=28. So the lightest molecules, NH3, are the fastest.

c.) This is beyond me.

4.) Decreasing the volume (by moving the piston) increases the pressure. Reducing the temperature by 20C = 20K decreases the pressure. You did not specify the new volume, so the final pressure cannot be calculated.

5.) a.) 2Na(s) + 2H2O ===> 2NaOH(aq) + H2(g)

b.) There are not enough data given to calculate.

c.) Because one cannot calculate /\H per g or per mole in b.), this cannot be calculated either.

d.) 17C = 290K, so 6.50LH2 x 740mmHg/760mmHg x 290K/273K = 6.72 L H2. You can also work this out with P1V1/T1 = P2V2/T2 or P2 = P1V1T2/V2T1

6.) a.) 1s2 2s2 2p6 3s2 3p6 4s2 3d2

b.) 3 2 -2 -1/2 and 3 2 -1 -1/2

c.) 1s2 2s2 2p6 3s2 3p6 3d2 Answer this question…