All categories

2 years ago

One question from Gases quiz

Chemistry

1 answer:

yulyashka [42]2 years ago

4 0

The pressure rises

As heat rises, so will the speed of the molecules

You might be interested in

A sample of CaCO3 (molar mass 100. g) was reported as being 30. percent Ca. Assuming no calcium was present in any impurities, c

natka813 [3]

Answer:

Approximately 75%.

Explanation:

Look up the relative atomic mass of Ca on a modern periodic table:

Ca: 40.078.

There are one mole of Ca atoms in each mole of CaCO₃ formula unit.

The mass of one mole of CaCO₃ is the same as the molar mass of this compound: $\rm 100\; g$ .
The mass of one mole of Ca atoms is (numerically) the same as the relative atomic mass of this element: $\rm 40.078\; g$ .

Calculate the mass ratio of Ca in a pure sample of CaCO₃:

$\displaystyle \frac{m(\mathrm{Ca})}{m\left(\mathrm{CaCO_3}\right)} = \frac{40.078}{100} \approx \frac{2}{5}$ .

Let the mass of the sample be 100 g. This sample of CaCO₃ contains 30% Ca by mass. In that 100 grams of this sample, there would be $\rm 30 \% \times 100\; g = 30\; g$ of Ca atoms. Assuming that the impurity does not contain any Ca. In other words, all these Ca atoms belong to CaCO₃. Apply the ratio $\displaystyle \frac{m(\mathrm{Ca})}{m\left(\mathrm{CaCO_3}\right)} \approx \frac{2}{5}$ :

$\begin{aligned} m\left(\mathrm{CaCO_3}\right) &= m(\mathrm{Ca})\left/\frac{m(\mathrm{Ca})}{m\left(\mathrm{CaCO_3}\right)}\right. \cr &\approx 30\; \rm g \left/ \frac{2}{5}\right. \cr &= 75\; \rm g \end{aligned}$ .

In other words, by these assumptions, 100 grams of this sample would contain 75 grams of CaCO₃. The percentage mass of CaCO₃ in this sample would thus be equal to:

$\displaystyle 100\%\times \frac{m\left(\mathrm{CaCO_3}\right)}{m(\text{sample})} = \frac{75}{100} = 75\%$ .

3 0

3 years ago

PLEASE HELP! 50 points and brainlyist to the correct answers!

Ronch [10]

1=k or d

2=A

Hope this helps

3 0

3 years ago

Identify the balanced single displacement reaction.

tekilochka [14]

CuCl2<span> + Fe ⟶ Cu + FeCI</span><span>2</span>

3 0

3 years ago

Read 2 more answers

An ionic compound has a slightly negative heat of solution in water. would you expect it to be soluble or insoluble in water?

Grace [21]

The ionic compound will be soluble in water.
The value of the heat of solution of a substance is one of the factors that determine whether a substance will dissolve or not. A negative heat of solution signifies that the reaction will be spontaneous, so the ionic compound will dissolve in water.

3 0

3 years ago

How would you increase the amount of garbage that is recycled at your school

melamori03 [73]

Make sure you have recycling bens in classrooms and in hallways. remind the teachers to keep on the students so they will get in the habit to recycle. This could reduce garbage and increase recycling! hope it works for you! :)

3 0

3 years ago