The answer is D. Use the equation PV=nRT
P=(.567mol)(.0821)(300K)/4.5L
Answer:
Magnesium and calcium belong to the second group i. e. alkaline earth metals. They are known as earth metals because they are extracted from the earth. They are very reactive elements. Their reactivity increases when we go from top to bottom because the outermost electrons goes farther from the nucleus i. e. atomic radius increases so less energy is needed for its removal.
Answer:
Mass = 153.48 g
Explanation:
Given data:
Volume of solution = 2.50 L
Molarity = 0.48 M
Mass required = ?
Solution:
Molarity = number of moles / volume in litter
Number of moles = Molarity × volume in litter
Number of moles = 0.48 M × 2.50 L
Number of moles = 1.2 mol
Mass of HI:
Number of moles = mass/molar mass
Mass = Number of moles × molar mass
Mass = 1.2 mol × 127.9 g/mol
Mass = 153.48 g
Answer:
C
Explanation:
The oxidation number of Sulphur in SO4^2- is;
x + 4(-2) = -2
x - 8 = -2
x = -2 + 8
x = 6
Now,
the oxidation number of sulphur in H2SO3 is
2 (1) + x + 3(-2) = 0
2 + x -6 = 0
-4 + x = 0
x = 4
Hence, the oxidation number of sulphur changed from +6 to +4 which signifies gain of two electrons as shown in option C.
