False :) :) :) :) :) :) :)
#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)
Atoms<span> are </span>arranged in molecular compounds in groups.
<span>
For </span>covalent compounds<span>: </span>
<span>consider drawing the lewis structure of the covalent compound in question, putting the atom which is least electronegative (save hydrogen) in the center.
</span>
Answer:
2.94
Explanation:
There is some info missing. I think this is the original question.
<em>A solution is prepared at 25 °C that is initially 0.38 M in chloroacetic acid (HCH₂ClCO₂), a weak acid with Ka= 1.3 x 10⁻³, and 0.44 M in sodium chloroacetate (NaCH₂CICO₂). Calculate the pH of the solution. Round your answer to 2 decimal places.</em>
<em />
We have a buffer system formed by a weak acid (HCH₂ClCO₂) and its conjugate base (CH₂CICO₂⁻ coming from NaCH₂CICO₂). We can calculate the pH using the Henderson-Hasselbalch equation.
pH = pKa + log [CH₂CICO₂⁻]/[HCH₂ClCO₂]
pH = -log 1.3 x 10⁻³ + log (0.44 M/0.38 M)
pH = 2.94
