#1: The element that loses electrons in a chemical reaction is said to have been which of the following?
A. reduced
B. oxidized
C. combusted
D. rusted
**idk, is it reduced or oxidized??
Answer: oxidized. The element that loses electrons increases its oxidation number (becomes more positve or less negative) and this is oxidation.
Which type of reaction occurs if one element gains electrons and another loses electrons?
A. combustion
B. synthesis
C. oxidation-reduction
D. double-displacement
**my answer: C
Yes, oxidation-reduction
#3: What is the oxidation number for phosphorus in H4P2O7?
A. +5
B. +3
C. +1
D. - 1
**my answer: A. +5
This is the way to calculate it 4(+1) + 2x + 7(-2) = 0 => x = +5
#4: What is the oxidation number for phosphorus in Na2HPO3?
A. +5
B. +3
C. +1
D. - 1
**my answer; B. +3
is that right??
Right
2(+1) + 1 + x + 3(-2) = 0 => x = 6 -1 -2 = 3 (positive)
