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4 years ago

__and_are examples of pure substances.

Chemistry

1 answer:

antiseptic1488 [7]4 years ago

6 0

Pure substances are either elements or compounds.

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An area experiences lack of moisture and precipitation. It also experiences high temperature and winds. Which severe weather eve

ddd [48]

Answer:

Drought

Explanation:

It would get really dry because no moisture and the lakes would dry up bc of lack of water

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3 years ago

a 150 g sample of water (initially at 45 C) is mixed with an unknown mass of water (initially at 84 C). the final temperature of

Evgesh-ka [11]

Answer : The unknown mass of water is, 200.3 grams.

Explanation :

In this problem we assumed that heat given by the hot body is equal to the heat taken by the cold body.

$q_1=-q_2$

$m_1\times c_1\times (T_f-T_1)=-m_2\times c_2\times (T_f-T_2)$

As,

$c_1=c_2$ = specific heat water

So,

$m_1\times (T_f-T_1)=-m_2\times (T_f-T_2)$

where,

$m_1$ = mass of water = 150 g

$m_2$ = mass of unknown water = ?

$T_f$ = final temperature of mixture = $67.3^oC$

$T_1$ = initial temperature of water = $45^oC$

$T_2$ = initial temperature of unknown water = $84^oC$

Now put all the given values in the above formula, we get

$150g\times (67.3-45)^oC=-m_2\times (67.3-84)^oC$

$m_2=200.3g$

Therefore, the unknown mass of water is, 200.3 grams.

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3 years ago

What happens when carbon dioxide gas is cooled to -78 degree Celsius

katrin2010 [14]

Answer:

At temperatures below −78 °C, carbon dioxide changes directly from a gas to a white solid called dry ice through a process called deposition.

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2 years ago

Hii pls help me with this ionic equation

slava [35]

Answer:

net ionic equation

$\boxed{ CaCO_3{}_{(s)} + 2H^{+} {}_{(aq.)} \rightarrow Ca^{2+} {}_{(aq.)} + H_2O_{(l)} + CO_2{}_{(g)} }$

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3 years ago

Type the correct answer in the box. Spell all words correctly. In which system are both energy and matter exchanged with the sur

Anna11 [10]

Answer:

open system

Explanation:

An open system is a system in which both energy and matter are exchanged with the surroundings.

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3 years ago

______and_____are examples of pure substances.

__and_are examples of pure substances.