Answer:
C. Their properties change completely.
Explanation:
The electron configurations of the elements show a periodic variation with increasing atomic number. Consequently, there are also periodic variations in physical and chemical behavior.
When atoms interact to form a chemical bond, they combine in order to <u>achieve a more stable electron configuration.</u> As a consequence, the compounds formed exhibit completely different properties.
For example, when solid magnesium burns in air, it forms both magnesium oxide and magnesium nitride, which are gases.
Answer:
0.91 atm is the partial pressure of just hydrogen gas.
Explanation:
Vapor pressure of water , p= 0.0313 atm
Partial pressure of hydrogen gas = 
Total pressure of the water vapors and hydrogen gas = P = 715 Torr
1 atm = 715 Torr

According Dalton's law of partial pressure:



0.91 atm is the partial pressure of just hydrogen gas.
Answer: molecular formula = C12H16O8
Explanation:
NB Mm CO2= 44g/mol
Mm H2O= 18g/mol
Moles of CO2 = 36.86/44=0.84mol
0.84mole of CO2 has 0.84 mol of C
Moles of H2O = 10.06/18= 0.56mol
1mol of H20 contains 1mol of O and 2 mol H,
Hence there are 0.56mol O and (0.56×2)mol H
Hence the compound contains
C= 0.84 mol H= 1.12mol O=0.56mol
Divide through by smallest number
C= 0.83/0.56= 1.5mol
H= 1.12/0.55= 2mol
O= 0.56/0.56= 1mol
Multiply all by 2 to have whole number of moles = 3:4:2
Hence empirical formula= C3H4O2
(C3H4O2)n = 288.38
[(12×3) + 4+(16×2)]n= 288.38
72n=288.38
n= 4
:. Molecular formula=(C3H4O2)4= C12H16O8
1:2:6? Ba(NO3)2 +Na2SO4 -----> BaSO4 + 2NaNO3
Ba(NO3)2
BaSO4
NaNO 3
Na2SO4
Answer:
of 0.056 M HF solution is 
Explanation:
cM 0 0
So dissociation constant will be:
Give c= 0.056 M and
= ?
Putting in the values we get:
Thus
of 0.056 M HF solution is 