Convert 6.620 × 102 kg to units of mg.

In a particular reaction, 53.8 g of liquid silicon tetrachloride is added to 65.0 g of solid magnesium to produce solid magnesiu

kotykmax [81]

Answer: Mg is the excess reactant for the forward reaction.

Explanation: It is a stoichiometry problem and solved with the help of given grams and using balanced equation. Grams of both the reactants are converted to moles and divided by their coefficients. The excess reactant is the one for which we get the highest number on doing above steps.

The balanced equation is:

$SiCl_4(l)+2Mg(s)\rightarrow 2MgCl_2(s)+Si(s)$

Molar mass of silicon tetra chloride is 169.9 gram per mol and the molar mass of Mg is 24.3 gram per mol.

$53.8gSiCl_4(\frac{1mol}{169.9g})$

= $0.317molSiCl_4$

$65.0gMg(\frac{1mol}{24.3g})$

= 2.67 mol Mg

From balanced equation, the coefficient of silicon tetra chloride is 1 and that of Mg is 2. So, we will divide the moles of silicon tetra chloride by 1 and that of Mg by 2 and see which one gives highest number.

For silicon tetra chloride, $\frac{0.317}{1}$ = 0.317

and for Mg, $\frac{2.67}{2}$ = 1.34

The highest number is for Mg and so the excess reactant for the forward reaction is Mg.

7 0

3 years ago

What is the initial temperature (in Celsius) of a 675 ml balloon if the

RoseWind [281]

Answer: 127 (3.s.f)

Explanation:

Boyle's law states that Volume x pressure = constant

Therefore let's first find the constant: 45 x 1900 = 85500

Then lets plug 675 ml and 85500 into the equation above:

675 x C = 85500

C = 127 (3 s.f.)

7 0

3 years ago

In the background information, it was stated that CaF2 has solubility, at room temperature, of 0.00160 g per 100 g of water. How

____ [38]

Answer:

2.05*10⁻⁵ moles of CF₂ can dissolve in 100 g of water.

12.82 moles of CaF₂ will dissolve in exactly 1.00 L of solution

Explanation:

First, by definition of solubility, in 100 g of water there are 0.0016 g of CaF₂. So, to know how many moles are 0.0016 g, you must know the molar mass of the compound. For that you know:

Ca: 40 g/mole
F: 19 g/mole

So the molar mass of CaF₂ is:

CaF₂= 40 g/mole + 2*19 g/mole= 78 g/mole

Now you can apply the following rule of three: if there are 78 grams of CaF₂ in 1 mole, in 0.0016 grams of the compound how many moles are there?

$moles=\frac{0.0016 grams*1 mole}{78 grams}$

moles=2.05*10⁻⁵

2.05*10⁻⁵ moles of CF₂ can dissolve in 100 g of water.

Now, to answer the following question, you can apply the following rule of three: if by definition of density in 1 mL there is 1 g of CaF₂, in 1000 mL (where 1L = 1000mL) how much mass of the compound is there?

$mass of CaF_{2}=\frac{1000 mL*1g}{1mL}$

mass of CaF₂= 1000 g

Now you can apply the following rule of three: if there are 78 grams of CaF₂ in 1 mole, in 1000 grams of the compound how many moles are there?

$moles=\frac{1000 grams*1 mole}{78 grams}$

moles=12.82

12.82 moles of CaF₂ will dissolve in exactly 1.00 L of solution

5 0

3 years ago

The dots in these cylinders represent the shape and

Elden [556K]

Answer:

A I think

Explanation:

Because plasma have ions and B is neutralized with two ions

8 0

3 years ago

A gaseous mixture of o2 and n2 contains 35.8 % nitrogen by mass. what is the partial pressure of oxygen in the mixture if the to

lubasha [3.4K]

The partial pressure is the amount of linguistic compound there is which makes the lagitude of the element 64.663

5 0

3 years ago