chemistry

You know ALL compounds are zero.
Ca is +2 each. 3*2 = 6+
You know O is -2 each. 8*-2 = -16
Since everything must add to zero, then
+6 +(-16) + 2P = 0
-10 + 2P = 0
2P = 10
P = +5 each

X-RAY DIFFRACTION OF AN UNKNOWN METAL, MIGHT BE DANGEROUS (10/10 points)
Last week you and a friend started an experiment to obtain the X-ray diffraction peaks of an unknown metal. Through these diffraction peaks you wanted to determine:
(a) whether the cell is SC, BCC, or FCC
(b) the (hkl) value of the peaks
(c) the lattice parameter a of the metal

Unfortunately, however, your friend (since he's not in 3.091) left MIT yesterday, not to return until next semester. All of the data that you could recover from the rubble in his room was the following:

[mathjaxinline] sin^2(\theta) [/mathjaxinline] 0.120 0.239 0.480 0.600 0.721 0.841 0.956
You also know that the metal is in the cubic crystal system and the wavelength of the X-rays used is [mathjaxinline] \lambda_{CuK_{\alpha}} [/mathjaxinline]. Using the following information, determine the information you were originally interested in (a, b, and c above).

a. Is the cell SC, BCC, or FCC?

SC<text>SC</text> - correctFCCBCC
b. Enter the hkl value of the peaks as a list separated by commas. Do not put spaces between the values. For instance:
[mathjaxinline] \theta_1,\theta_2,... = (100),(111),... [/mathjaxinline]

(100),(110),(111),(200),(102),(112),(202) - correct
c. Enter the lattice parameter a in Angstroms.

2.24 - correct