10 and 10
9 and 9
11 and 9
9 and 11
Correct answer is D
X- means one excess electron, hence 9 protons while Y +/- means one deficit electron hence 11 protons X and Y = 9 and 11
5
4
3
2
Correct answer is C
The atomic number of phosphorus is 15 and the 3p sublevel has three unpaired electrons.
has formula XY
is likely to be ionic
contains X2+ ions
contains Y- ions
Correct answer is A
The compound formed by a mixture of X and Y will be \(XY_{2}\) not XY.
1.00
2.00
3.00
4.00
Correct answer is A
PV = nRT
2.93 x 8.2 = 0.082 x 293 xn
∴ n = (2.93 x8.2) / (0.082 x 293)
n = 1
220 cm3
225 cm3
230 cm3
235 cm3
Correct answer is B
P1V1 = P2V2 ∴ 750 x 228 = 760 V2
V2 = (750 x 228 cm3) / (760) = 225 cm3