Answer:
In a physical change the appearance or form of the matter changes but the kind of matter in the substance does not. However in a chemical change, the kind of matter changes and at least one new substance with new properties is formed.
Answer:
- <u>1. Equation: 2x + 3 = 9x - 11</u>
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- <u>2. Each row has 2 chairs</u>
Explanation:
The variable x represents the number of chairs in each row.
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<u>1. She can form 2 rows of a given length with 3 chairs left over.</u>
Thus, she has:
number of rows number of chairs in chairs number of chairs
each row left over she has
2 x 3 2x + 3
<u>2. She can form 9 rows of the same length if she gets 11 more chairs.</u>
That means that she is short in 11 chairs to have 9x chairs, or that she has 11 less chairs than 9x chairs. Then she has:
<u>3. Equation:</u>
Then, number of chairs she has is 2x + 3 and, also, 9x - 11, which allows to set the equation:
<u>4. Solve the equation:</u>
Therefore, each row has 2 chairs, and she has 2x + 3 = 4 + 3 = 7 chairs.
We have to complete all the given reactions.
1. Fe(s) + CuCl₂ → Cu + FeCl₂
2. Cu(s) + FeCl₂(aq) → NR (no reaction takes place)
3. K(s) + NiBr2(aq) → NR (no reaction takes place)
4. Ni(s) + KBr(aq) → K + NiBr₂
5. Zn(s) + Ca(NO₃)₂(aq) → NR (no reaction)
6. Ca(s) + Zn(NO₃)₂(aq) → Zn(s) + Ca(NO₃)₂(aq)
D: urethra
20 characters necessary for answer so that's what this typing Is for
Answer:
Oxygen is in excess.
Explanation:
The coefficients of the balanced equation create a mole ratio that shows the ratio of how many reactants are used up and products are created.
The mole ratio of Mg to O2 in this equation is 2:1, which means that for every two moles of Mg used, there will be 1 mole of O2 used.
If we have 3.00 moles of Mg, we will only need 1.5 moles of oxygen to completely burn the Mg. Therefore, when all 3.00 moles of Mg are used, there will still be some of the 2.20 moles of oxygen remaining.
