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3 years ago

I need help help me please

Chemistry

1 answer:

Rzqust [24]3 years ago

3 0

Answer:

C is the correct answer.

Explanation:

We can eliminate some answers immediately:

A is incorrect because nitrogen and hydrogen do not change their identity, they just combine into a new molecule that contains them. Notice how there are 2 nitrogen atoms and 6 hydrogen atoms on both sides of the equation.

B is incorrect because the first law of thermodynamics tells us that matter and energy will always be conserved, so the mass of the products must be equal to the mass of the reactants, not less than the mass of the reactants.

C is correct because balanced chemical equations help chemists predict how much product will form from certain amounts of reactants.

D is incorrect because this equation is showing the exact opposite. Molecular hydrogen and nitrogen can combine stoichiometrically to form ammonia.

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Why does such a small decrease in pH mean such a large increase in acidity?

den301095 [7]

Answer:

pH is an index of how many protons, or hydrogen ions (H+) are dissolved and free in a solution. The pH scale goes from 0 to 14. A fluid with a pH of 7 is neutral. Below 7, it is acidic; above 7, it is alkaline.

The more below or above 7 a solution is, the more acidic or alkaline it is. The scale is not linear—a drop from pH 8.2 to 8.1 indicates a 30 percent increase in acidity, or concentration of hydrogen ions; a drop from 8.1 to 7.9 indicates a 150 percent increase in acidity. Bottom line: Small-sounding changes in ocean pH are actually quite large and definitely in the direction of becoming less alkaline, which is the same as becoming more acidic.

If you think about it, we use descriptive words like this all the time. A person who stands 5’5” tall and weighs 300 pounds isn’t thin. If he loses 100 pounds, he still won’t be thin, but he will be thinner than he was before he went on the diet. (And we are more likely to comment that he’s looking trimmer than to say he’s not as fat as he used to be.)

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2 years ago

What is the sequence of coefficients that will balance the following decomposition reaction of dihydrogen monosulfide? H₂S ----&

RUDIKE [14]

8 S

In this case you must start balancing the sulfur to have 8 on each side of the reaction. So:

Answer:

Explanation:

The law of conservation of matter states that since no atom can be created or destroyed in a chemical reaction, the number of atoms that are present in the reagents has to be equal to the number of atoms present in the products.

Then, you must balance the chemical equation. For that, you must first look at the subscripts next to each atom to find the number of atoms in the equation. If the same atom appears in more than one molecule, you must add its amounts.

The coefficients located in front of each molecule indicate the amount of each molecule for the reaction. This coefficient can be modified to balance the equation, just as you should never alter the subscripts.

By multiplying the coefficient mentioned by the subscript, you get the amount of each element present in the reaction.

Then, taking into account all of the above, you can determine the amount of elements on each side of the equation:

Left side: 2 H and 1 S

Right side: 2 H and 8 S

In this case you must start balancing the sulfur to have 8 on each side of the reaction. So:

8 H₂S → H₂ + S₈

Now the amount of elements on each side of the equation:

Left side: 16 H and 8

Right side: 2 H and 8 S

Now you need to start balancing the hydrogen to get the same amount from each side of the reaction. So:

8 H₂S → 8 H₂ + S₈

Now the amount of elements on each side of the equation:

Left side: 16 H and 8

Right side: 16 H and 8 S

The balanced reaction is:

8 H₂S → 8 H₂ + S₈

3 0

2 years ago

The octane number of gasoline is a measure of octane activity. The octane activity is determined by comparing the engine perform

Semmy [17]

Answer:

A. True

Explanation:

The octane number is determined by comparing the characteristics of gasoline to isooctane (2,2,4-trimethylpentane) and heptane. The correct option is option A.

Basically, the higher the octane number, the greater the resistance of the gasoline to knocking.

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2 years ago

People in the United States know that water boils at 212 degrees Fahrenheit. In Europe, people know that water boils at 100 degr

snow_tiger [21]

No, the water is not different it is just that the units of measurement in the US is different then those units in Europe. This is similar to how the US uses miles and Europe uses kilometers

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3 years ago

Which of the following is a measurement of an object's mass?

Brilliant_brown [7]

Answer:

10 Kilograms

Explanation:

"millimetres" is a unit of measurement and is used for measuring distances.

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:kilograms" is the one used for measuring mass

5 0

3 years ago