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3 years ago

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Chemistry

1 answer:

Sedbober [7]3 years ago

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Answer:

I don't know I'm sorry I will tell you another answer asks me to

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A sample of chemical X is found to contain 5.0 grams of oxygen, 10.0 grams of carbon, and 20.0 grams of nitrogen. The law of def

frozen [14]

Answer: 75 grams sample of chemical X should contain 21.43 grams of carbon

Explanation: The law of definite proportion states that a given chemical compound always contains its component elements in fixed ratio.

From the question, chemical X contains 5.0 grams of oxygen, 10.0 grams of carbon, and 20.0 grams of nitrogen.

Sum up the masses

5.0g + 10.0g + 20.0g = 35.0g

This means, 10.0 grams of carbon are present in 35.0 grams of chemical X.

Now, to the determine the mass of carbon that 75 gram sample of chemical X should contain,

According to the law of definite proportion, the component elements of a given chemical compound are in fixed ratio. Therefore,

If 35.0g of chemical X contains 10.0g of carbon

Then, 75 g of chemical X will contain

(75 × 10) / 35 g

= 21.43 grams

Hence, 75 grams sample of chemical X should contain 21.43 grams of carbon.

4 0

3 years ago

Read 2 more answers

2 FONS

stiv31 [10]

Answer:

C. It decreases by a factor of 4

Explanation:

F1 = kq1*q2/r²

F2 = kq1*q2/(2r)² = kq1*q2/(4r²) = kq1*q2/(r²*4) = F1/4

7 0

3 years ago

Explain why copper is used for the roofs of some buildings and magnesium is not.

Scrat [10]

Answer:

Because of the less reactivity of copper.

Explanation:

As well as being resistant to the elements and thereby less likely to be affected by rainfall, hail, and mildew than other types of roofing, copper is also one of the most fireproof materials available. Copper is also highly resistant to thermal changes and thereby doesn't deteriorate quickly.

Magnesium would also corrode PDQ. Magnesium sheeting would also pose an unacceptably high fire hazard.

3 0

2 years ago

A student added 5 grams of calcium chloride, a white solid substance, to 15 grams of water at 220 C. Several observations were m

umka21 [38]

Answer:

Explanation:

A The calcium chloride dissolves in solution

B The mass of the solution totals 20 g

C The temperature of the solution is 35 degrees

D The solution became lighter in color

The correct answer would be that the solution became lighter in color.

An increase in temperature can also be considered a sign of a chemical reaction but in this case, the dissolution of calcium chloride in water is in itself exothermic.

A change in the mass of the final solution could also be considered a sign of a chemical reaction but in this case, the total mass equals the addition of the individual masses of the reactant.

The dissolution of calcium chloride in water is not enough as evidence of a chemical reaction. Dissolution can be a physical change of which, the evaporation of the water would retrieve the solute.

A change in color, however, is one of the evidence to establish that a chemical reaction has occurred.

The correct option is D.

4 0

3 years ago

Compressing a sample of hydrogen gas to one half its initial volume will have what effect on its pressure?

avanturin [10]

By Boyle's Law pV = constant, halfing the volume would require doubling the pressure to maintain the constant. Hence, pressure doubles.

6 0

4 years ago

Read 2 more answers