Let's use the example: H2O ---> H2 + O2
We find how many elements of a product are on one side and how many elements on the other side.
Reactant: H=2 O=1
Product: H=2 O=2
We need to make the same amount of hydrogen and oxegyn atoms on each side, regardless of how high the numbers are, and we do this by adding coefficients to the compounds.
Reactant: H=4 O=2
Product : H=4 O=2
2 H2O---> 2 H2 + O2
Answer:
tama yon sagot nya gayahin mo nalang
Answer:
14.93 g
Explanation:
First we <u>convert 1.2 x 10²³ atoms of arsenic (As) into moles</u>, using <em>Avogadro's number</em>:
- 1.2 x 10²³ atoms ÷ 6.023x10²³ atoms/mol = 0.199 mol As
Then we can<u> calculate the mass of 0.199 moles of arsenic</u>, using its<em> molar mass</em>:
- 0.199 mol * 74.92 g/mol = 14.93 g
Thus, 1.2x10²³ atoms of arsenic weigh 14.93 grams.
#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)
1. is not a step in most scientific investigations.
