Salt solutions can be __________ to give solid salts. What word completes this sentence?

1. Suppose 0.7542 g of magnesium reacts with excess oxygen to form magnesium oxide as the only product, what would be the theore

Alina [70]

Answer :

(1) The theoretical yield of product, $MgO$ is, 1.257 grams.

(2) The percent yield of $MgO$ is, 64.13 %

(3) If the percent yield is calculated to be over 100% then there might be some impurity present in the desired product.

Solution : Given,

Mass of Mg = 0.7542 g

Molar mass of Mg = 24 g/mole

Molar mass of MgO = 40 g/mole

First we have to calculate the moles of Mg.

$\text{ Moles of }Mg=\frac{\text{ Mass of }Mg}{\text{ Molar mass of }Mg}=\frac{0.7542g}{24g/mole}=0.03142moles$

Now we have to calculate the moles of $MgO$

The balanced chemical reaction is,

$2Mg(s)+O_2(g)\rightarrow 2MgO(s)$

From the reaction, we conclude that

As, 2 mole of $Mg$ react to give 2 mole of $MgO$

So, 0.03142 moles of $Mg$ react to give 0.03142 moles of $MgO$

Now we have to calculate the mass of $MgO$

$\text{ Mass of }MgO=\text{ Moles of }MgO\times \text{ Molar mass of }MgO$

$\text{ Mass of }MgO=(0.03142moles)\times (40g/mole)=1.257g$

Theoretical yield of $MgO$ = 1.257 g

Experimental yield of $MgO$ = 0.8922 g

Now we have to calculate the percent yield of $MgO$

$\% \text{ yield of }MgO=\frac{\text{ Experimental yield of }MgO}{\text{ Theretical yield of }MgO}\times 100$

$\% \text{ yield of }MgO=\frac{0.8922g}{1.257g}\times 100=70.97\%$

Therefore, the percent yield of $MgO$ is, 70.97 %

If the percent yield is calculated to be over 100% then the product would be greater than 1.257 g which indicates that there might be some impurity present in the desired product.

4 0

2 years ago

HELP

agasfer [191]

Answer:

3.02× 10²⁴ atoms

Explanation:

Given data:

Number of nitrogen atoms = ?

Number of moles of N₂O = 2.51 mol

Solution:

1 mole contain 2 mole of nitrogen atoms.

2.51 × 2 = 5.02 mol

According to Avogadro number,

1 mole = 6.022 × 10²³ atoms

5.02 mol × 6.022 × 10²³ atoms / 1 mol

30.2 × 10²³ atoms

3.02× 10²⁴ atoms

5 0

1 year ago

Classify the following as a type of potential energy or kinetic energy (use the letters K or P)

Zanzabum

K, P, K, K, P, K, K, P, K, P. If it is moving, it is kinetic, if it isn't, it's potential. the sugar one is a little tricky using that method though, because we generally consider this in terms of spacial movement, but sugar holds energy which is later released by your body to allow you to move.the chemical bonds have potential energy because they release energy when broken.

5 0

1 year ago

Read 2 more answers

The adult blue whale has a lung capacity of 5.0×103 L5.0×103 L. Calculate the mass of air (assume an average molar mass 28.98 g/

andrew11 [14]

Answer:

The mass of the air is 6920.71g

Explanation:

Step 1:

Data obtained from the question. This includes the following:

Volume (V) = 5.0x10^3 L

Molar Mass of air (M) = 28.98 g/mol

Temperature (T) = 0.2°C

Pressure (P) = 1.07 atm

mass air (m) =?

Number of mole (n) =?

Recall:

Gas constant (R) = 0.082atm.L/Kmol

Step 2:

Conversion of celsius temperature to Kelvin temperature.

K = °C + 273

°C = 0.2°C

K = °C + 273

K = 0.2°C + 273

K = 273.2 K

Therefore, the temperature (T) = 273.2 K

Step 3:

Determination of the number of mole of air.

Applying the ideal gas equation PV = nRT, the number of mole n, can be obtained as follow:

PV = nRT

1.07 x 5.0x10^3 = n x 0.082 x 273.2

Divide both side by 0.082 x 273.2

n = (1.07 x 5.0x10^3)/(0.082 x 273.2)

n = 238.81 moles

Step 4:

Determination of the mass of air. This is illustrated below:

Number of mole of air = 238.81 moles

Molar Mass of air = 28.98 g/mol

Mass of air =.?

Mass = number of mole x molar Mass

Mass of air = 238.81 x 28.98

Mass of air = 6920.71g

3 0

2 years ago

Which of the following statements is not true of the combustion of an organic compound?

Novay_Z [31]

<em>The following statements are not true of the combustion of an organic compound is </em>

<em>C. it can also be described as a synthesis reaction </em>

<h3><em>Further explanation</em></h3>

Organic compounds have a characteristic that there is a chain of carbon atoms, while in inorganic does not have a chain of carbon atoms

The reaction of a substance with oxygen is called a combustion reaction

Perfect combustion of carbon compounds will get CO2 gas, whereas if it is not perfect it will produce CO gas

Identification of carbon compounds can usually be done by flowing it into lime water which produces turbid water because of the reaction of CO2 with Ca(OH)₂ to form CaCO₃

Burning organic samples will convert C atoms to CO₂ and H to H₂O

We see the answer choices

1. Oxygen is included in the reactants in the combustion process

So the answer is correct

2. Energy is released during combustion because the reaction is exothermic or releases heat with a negative enthalpy of combustion

So the answer is correct

3. A decomposition reaction is the decomposition reaction of a compound into its constituent elements. In combustion reactions, occur decomposition, not a formation reaction

So the answer is wrong

4. CO₂ is the result of combustion,

So the answer is correct

<h3><em>Learn more</em></h3>

properties of hydrocarbons brainly.com/question/4619751

<h3><em>Answer details </em></h3>

Grade: Senior High School

Subject: Chemistry

Chapter: Hydrocarbons

Keywords: combustion, organic, inorganic, a carbon chain

7 0

1 year ago