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algol [13]
3 years ago
8

Which element had the longest effect on human history?

Chemistry
1 answer:
Dovator [93]3 years ago
6 0
Oxygen I guess :)))       

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Is apple juice a homogeneous mixture or a heterogeneous mixture
Solnce55 [7]

If you mean the industrialized apple juice then yes. Even though there are several different compounds and some of them aren't actually dissolved in the liquid, since you can't actually distinguish between them using only your eyes and they do no separate naturally it is actually a homogeneous mixture.


5 0
3 years ago
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A solution prepared by mixing 10 ml of 1 m hcl and 10 ml of 1.2 m naoh has a ph of
blagie [28]

Answer: pH of resulting solution will be 13

Explanation:

pH is the measure of acidity or alkalinity of a solution.

Moles of H^+ ion = Molarity\times {\text {Volume in L}}=1M\times 0.01L=0.01mol

Moles of OH^- ion = Molarity\times {\text {Volume in L}}=1.2M\times 0.01L=0.012mol

HCl+NaOH\rightarrow NaCl+H_2O

For neutralization:

1 mole of H^+ ion will react with 1 mole of OH^- ion

0.01 mol of H^+  ion will react with =\frac{1}{1}\times 0.01mole of OH^- ion

Thus (0.012-0.01)= 0.002 moles of OH^- are left in 20 ml or 0.02 L of solution.

[OH^-]=\frac{0.002}{0.02L}=0.1M

pOH=-log[OH^-]

pOH=-log[0.1]=1

pH+pOH=14

pH=14-1=13

Thus the pH of resulting solution will be 13

7 0
3 years ago
NEED HELP ASAP LAST QUESTION CANT GET WRONG !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
yaroslaw [1]

A local community needs to provide more electricity for its growing population. Currently, the community's electricity needs are met by coal-burning power plants several kilometres away. Citizens are concerned that burning more coal will produce too much air pollution.

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B.  solar energy

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8 0
3 years ago
if you obtain the powder of a mineral by rubbing a mineral on a porcelain plate, which property have u observed?
charle [14.2K]
you have observed streak :)
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4 years ago
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50 POINTS PLEASE HELP!
rjkz [21]

A physical change has occured, Boiling water is a physical change not a chemical one, now if you're talking about the electric current, that had not changes either. it may rearrange the molecules, but it does not change the fundamental properties of the substance.

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3 years ago
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