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2 years ago

Are elements considered to be substances?

Chemistry

1 answer:

Schach [20]2 years ago

7 0

Answer:

C. Yes, because they have a definite composition.

Explanation:

<h2><u><em>PLEASE MARK AS BRAINLIEST!!!!!</em></u></h2>

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Which property of water makes it helpful to use in car radiators?

Nezavi [6.7K]

The correct answer is<span> C) Water takes long to heat and cool down than other liquids.

It doesn't climb up the sides of a tube any more than other solutions do, and being a universal solvent has nothing to do with radiators. It does however take a long time to heat and cool down since you don't have a 100+ celsius burner to heat it up in an instant.</span>

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2 years ago

Living organisms make their own carbon

san4es73 [151]

Where’s the question is this a true or false question

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3 years ago

A mixture of 15.0 g of the anesthetic halothane (C2HBrClF3 197.4 g/mol) and 22.6 g of oxygen gas has a total pressure of 862 tor

AlexFokin [52]

Answer : The partial pressure of $C_2HBrClF_3$ and $O_2$ are, 84 torr and 778 torr respectively.

Explanation : Given,

Mass of $C_2HBrClF_3$ = 15.0 g

Mass of $O_2$ = 22.6 g

Molar mass of $C_2HBrClF_3$ = 197.4 g/mole

Molar mass of $O_2$ = 32 g/mole

First we have to calculate the moles of $C_2HBrClF_3$ and $O_2$ .

$\text{Moles of }C_2HBrClF_3=\frac{\text{Mass of }C_2HBrClF_3}{\text{Molar mass of }C_2HBrClF_3}=\frac{15.0g}{197.4g/mole}=0.0759mole$

and,

$\text{Moles of }O_2=\frac{\text{Mass of }O_2}{\text{Molar mass of }O_2}=\frac{22.6g}{32g/mole}=0.706mole$

Now we have to calculate the mole fraction of $C_2HBrClF_3$ and $O_2$ .

$\text{Mole fraction of }C_2HBrClF_3=\frac{\text{Moles of }C_2HBrClF_3}{\text{Moles of }C_2HBrClF_3+\text{Moles of }O_2}=\frac{0.0759}{0.0759+0.706}=0.0971$

and,

$\text{Mole fraction of }O_2=\frac{\text{Moles of }O_2}{\text{Moles of }C_2HBrClF_3+\text{Moles of }O_2}=\frac{0.706}{0.0759+0.706}=0.903$

Now we have to partial pressure of $C_2HBrClF_3$ and $O_2$ .

According to the Raoult's law,

$p^o=X\times p_T$

where,

$p^o$ = partial pressure of gas

$p_T$ = total pressure of gas

$X$ = mole fraction of gas

$p_{C_2HBrClF_3}=X_{C_2HBrClF_3}\times p_T$

$p_{C_2HBrClF_3}=0.0971\times 862torr=84torr$

and,

$p_{O_2}=X_{O_2}\times p_T$

$p_{O_2}=0.903\times 862torr=778torr$

Therefore, the partial pressure of $C_2HBrClF_3$ and $O_2$ are, 84 torr and 778 torr respectively.

6 0

2 years ago

Suppose you have 15.0 ml of zinc. What volume of aluminum would have the same mass as the zinc?

Black_prince [1.1K]

Answer:

$\large \boxed{\text{41.2 cm}^{3}}$

Explanation:

1. Mass of zinc

The density of zinc is 7.14 g/cm³

D = m/V

$\begin{array}{rcl}7.14 & = & \dfrac{m}{15.0}\\\\m & = & 7.14 \times 15.0\\& = & \text{107.1 g}\\\end{array}\\$

2. Volume of aluminium

The density of aluminium is 2.60/cm³.

$\begin{array}{rcl}2.60 & = & \dfrac{107.1}{V}\\\\2.60V & = & 107.1\\V& = &\dfrac{107.1}{2.60}\\\\& = &\textbf{41.2cm}^{\mathbf{3}}\\\end{array}\\\large \boxed{\textbf{41.2 cm}^{\mathbf{3}}}\text{ of aluminium have the same mass as 15.0 cm$^{3}$ of zinc.}$

5 0

3 years ago

Which of the following correctly describes a property of an atom?

Masteriza [31]

Answer:

it has an equal number of neutrons and electrons

Explanation:

Number of protons always equal number of electron, but that's the case with a neutral atom. A neutral atom is an atom of any element that has no electric charge over it. This implies that it has same number of protons and electrons in it.

3 0

2 years ago