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Trava [24]
3 years ago
9

State whether the following is an example of a physical or chemical change:! 21. Burning a log: ________________________________

! 22. Folding a piece of paper: _________________________! 23. Freezing water: _________________________! 24. Bending a copper wire. _________________________!
Chemistry
2 answers:
lyudmila [28]3 years ago
6 0

Answer:

Physical change

Explanation:

Because it doesn't require any chemical to change

Ivan3 years ago
5 0

Answer:

Physical change

Physical change

Physical change

Physical change

Explanation:

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X ml - <span>25% alcohol mixture
y ml - </span><span>90% alcohol mixture

x+y = 455 

0.25x ml alcohol in </span>x ml of  25% alcohol mixture
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0.75*455= 341.25 ml alcohol in 455 ml of  75% alcohol mixture

0.25x+0.9y=341.25 

System of equations:

x+y = 455 /*(-0.25) ------> -0.25x-0.25y = -0.25*455 
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-0.25x-0.25y=-113.75
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0.25x+0.9y-0.25x-0.25y=341.25-113.75
0.65y =227.5
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hich quantity describes how spread out a set of data is? O A. Standard deviation O B. Percent error O C. Line of best fit D. Mea
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The answer to this is B.

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A mixture of co(g) and h2(g) is pumped into a previously evacuated 2l reaction vessel the total pressure of the reaction system
swat32

Answer is: total pressure of the system is 2.4 atm.

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the correct answer is B

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