______________Helps the earth continue to go around the sun

8. The best way to obtain pure, solid household salt from a solid mixture of household salt and sand is to:

dedylja [7]

The best way to obtain pure, solid household salt from a solid mixture of household salt and sand is to "add water, stir, filter and evaporate the filtrate".

Option: C

Explanation:

The salt and sand can be separated on the basis of solubility, as we know the salt is chemically known as sodium chloride, which have good solubility in water. The most general method is the mixture is taken into a flask or beaker and water is added with stirring, where salt get dissolved and sand remain as it is, because NaCl is capable enough to form hydrogen bonding with water, while sand have absence of such property. Then this solution containing insoluble sand is filtered by using filter paper. The sand is received in filter paper while filtrate in beaker is evaporated by boiling it in order to receive salt as residue.

8 0

3 years ago

This group has characteristics including: brittleness, insulators/poor conductors, and are often found as gases.

bagirrra123 [75]

Answer:

The answer is non-metals

Explanation:

6 0

2 years ago

Read 2 more answers

During an experiment, 95 grams of calcium carbonate reacted with an excess amount of hydrochloric acid. If the percent yield of

almond37 [142]

Answer:

Actual yield: 86.5 grams.

Explanation:

How many moles of formula units in 95 grams of calcium carbonate $\rm CaCO_3$ ?

Refer to a modern periodic table for relative atomic mass data:

Ca: 40.078;
C: 12.011;
O: 15.999.

Formula mass of $\rm CaCO_3$ :

$M(\mathrm{CaCO_3}) = \underbrace{1\times 40.078}_{\rm Ca} + \underbrace{1\times 12.011}_{\rm C} + \underbrace{3\times 15.999}_{\rm O} = \rm 100.086\;g\cdot mol^{-1}$ .

$\displaystyle n(\mathrm{CaCO_3}) = \frac{m(\mathrm{CaCO_3})}{M(\mathrm{CaCO_3})} = \rm \frac{95\;g}{100.086\;g\cdot mol^{-1}} = 0.949184\;mol$ .

How many moles of $\rm CaCl_2$ will be produced?

The coefficient in front of $\rm CaCO_3$ in the chemical equation is the same as that in front of $\rm CaCl_2$ . That is:

$\displaystyle \frac{n(\rm CaCl_2)}{n(\rm CaCO_3)} = 1$ .

$\displaystyle n(\mathrm{CaCl_2}) = n(\mathrm{CaCO_3})\cdot \frac{n(\rm CaCl_2)}{n(\rm CaCO_3)} = n(\mathrm{CaCO_3}) = \rm 0.949184\;mol$ .

What's the theoretical yield of calcium chloride? In other words, what's the mass of $\rm 0.949184\;mol$ of $\rm CaCl_2$ ?

Again, refer to a periodic table for relative atomic data:

Ca: 40.078;
Cl: 35.45.

$M(\mathrm{CaCl_2}) = \underbrace{1\times 40.078}_{\rm Ca} + \underbrace{2\times 35.45}_{\rm Cl} = \rm 110.978\;g\cdot mol^{-1}$ .

$\begin{aligned}m(\mathrm{CaCl_2}) &= n(\mathrm{CaCl_2})\cdot M(\mathrm{CaCl_2})\\ &= \rm 0.949184\;mol\times 110.978\;g\cdot mol^{-1}\\ &= \rm 105.339\; g\end{aligned}$ .

What's the actual yield of calcium chloride?

$\displaystyle \text{Percentage Yield} = \frac{\text{Actual Yield}}{\text{Theoretical Yield}}\times 100\%$ .

$\displaystyle \begin{aligned}\text{Actual Yield} &= \text{Theoretical Yield}\cdot \frac{\text{Percentage Yield}}{100\%}\\ &=\rm 105.339\; g \times \frac{82.15\%}{100\%}\\&= \rm 86.5\;g \end{aligned}$ .

8 0

3 years ago

The basic principle in balancing a chemical equation is to ______. View Available Hint(s) The basic principle in balancing a che

OlgaM077 [116]

Answer:

have the same number of atoms of each element in the reactants and in the products

Explanation:

The basic principle in balancing a chemical equation would simply be to have the same number of atoms of each element in the reactants and in the products.

A balanced chemical equation is one that has the same number of atoms of each element on the reactant and the product's side of the equation. For example, consider the equation below:

$H_2 + O_2 --> H_2O$

On the reactant's side, there are 2 atoms of H and O while there are 2 atoms of H and 1 atom of O on the product's side. This is an imbalanced equation. In order for it to be balanced, the number of atoms of H and O on the reactant side must be equal to the number of H and O on the product side as below.

$2H_2 + O_2 --> 2H_2O$

5 0

3 years ago

The atmosphere surrounding Earth helps to maintain the various climates found around the world and keeps Earth from becoming ext

riadik2000 [5.3K]

Answer:

The atmosphere traps heat energy from the Sun and energy radiated from Earth's surface helping to maintain Earth's climate

Explanation:

Earth's atmosphere keeps much of the Sun's energy from escaping into space. This process, called the greenhouse effect, keeps the planet warm enough for life to exist. The atmosphere allows about half of the Sun's heat energy (50%) to reach Earth's surface.

4 0

2 years ago