9. Light is used in photosystem II and photosystem I to

Use the equation to determine what mass of FeS must react to form 326 g of FeCl2.

iogann1982 [59]

Answer:

We need 226 grams of FeS

Explanation:

Step 1: Data given

Mass of FeCl2 = 326 grams

Molar mass FeCl2 = 126.75 g/mol

Step 2: The balanced equation

FeS + 2 HCl → H2S + FeCl2

Step 3: Calculate moles FeCl2

Moles FeCl2 = 326 grams / 126.75 grams

Moles FeCl2 = 2.57 moles

Step 4: Calculate moles FeS needed

For 1 mol H2S and 1 mol FeCl2 produced, we need 1 mol FeS and 2 moles HCl

For 2.57 moles FeCl2 we need 2.57 moles FeS

Step 5: Calculate mass FeS

Mass FeS = 2.57 moles * 87.92 g/mol

Mass FeS = 226 grams FeS

We need 226 grams of FeS

4 0

3 years ago

In distillation,separation is achieved by difference in---

Arisa [49]

Answer:

relative volatility.

mark me brainliestt :))

5 0

3 years ago

Read 2 more answers

An average person expends about 845 kilojoules of energy per hour of walking. Suppose a person eats 2 baked potatoes with butter

ExtremeBDS [4]

Answer:

$\large\boxed{2hours}$

Explanation:

You will need to use the conversion between food calories, calories and joules.

$1\text { nutritional calorie }= 1,000cal\\ \\ 1cal=4.184joule$

From a nutritional table (from the internet) you can obtain the amount of nutritional calories for each type macronutrient: carbohydrates, protein, and fat.

Macronutrient food calories

Carbohydrate 4 cal/g

Protein 4 cal/g

Fat 9 cal/g

To convert food calories to regular calories, mutiply by the conversion factor:

$1=1,000cal/\text{nutritional calorie}$

Macronutrient calories

Carbohydrate 4,000 cal/g

Protein 4,000 cal/g

Fat 9,000 cal/g

To convert regular calories to joules, multiply by the conversion factor:

$1=4.184 joule/1cal$

Macronutrient energy in joules

Carbohydrate 16,736 joule/g

Protein 16,736 joule/g

Fat 37,656 joule/g

Now you can multiply the grams of each macronutrient in one potato by its energy content:

Macronutrient energy/gram × grams = total energy

Carbohydrate 16,736 joule/g × 37 g = 619,232 joules

Protein 16,736 joule/g × 4.3 g = 71,968.8 joules

Fat 37,656 joule/g × 4 g = 150,624 joules

Total = 619,232 joules + 71,968.8 joules + 150,624 joules = 841,820.8 joules.

Since they are two potatoes, multiply by 2: × 841,820.8 joules = 1,683,641.6 joules.

Divide by 1,000 to convert to kilojoules = 1,683.64 kilojoules

Divide the total energy from the two potatoes by the energy that an average person expend per hour of walking (845 kilojoules of energy per hour):

$1,683.64kilojoules/845kilojouesl/hour=1.99hours\approx 2hours$

7 0

3 years ago

Calculate the specific heat of the substance if 373 J is required to raise the temperature of a 312 gram sample by 25°C?

I am Lyosha [343]

Explanation:

Q = 373J

∆∅ = 25°C

m = 312g

c = x

Q = mc∆∅

373 = 312(x)(25)

373 = 7800x

x = 373/7800

x = 0.0478J/(g°C)

4 0

3 years ago

Androstenedione, which contains only carbon, hydrogen, and oxygen, is a steroid hormone produced in the adrenal glands and the g

Gennadij [26K]

Answer: The molecular formula for androstenedione is, $C_{19}H_{26}O_2$

Explanation:

The chemical equation for the combustion of hydrocarbon having carbon, hydrogen and oxygen follows:

$C_xH_yO_z+O_2\rightarrow CO_2+H_2O$

where, 'x', 'y' and 'z' are the subscripts of Carbon, hydrogen and oxygen respectively.

We are given:

Mass of $CO_2=5.527g$

Mass of $H_2O=1.548g$

We know that:

Molar mass of carbon dioxide = 44 g/mol

Molar mass of water = 18 g/mol

For calculating the mass of carbon:

In 44 g of carbon dioxide, 12 g of carbon is contained.

So, in 5.527 g of carbon dioxide, $\frac{12}{44}\times 5.527=1.507g$ of carbon will be contained.

For calculating the mass of hydrogen:

In 18 g of water, 2 g of hydrogen is contained.

So, in 1.548 g of water, $\frac{2}{18}\times 1.548=0.172g$ of hydrogen will be contained.

For calculating the mass of oxygen:

Mass of oxygen in the compound = $(1.893g)-[(1.507g)+(0.172g)]=0.214g$

To formulate the empirical formula, we need to follow some steps:

Step 1: Converting the given masses into moles.

Moles of Carbon = $\frac{\text{Given mass of Carbon}}{\text{Molar mass of Carbon}}=\frac{1.507g}{12g/mole}=0.126moles$

Moles of Hydrogen = $\frac{\text{Given mass of Hydrogen}}{\text{Molar mass of Hydrogen}}=\frac{0.172g}{1g/mole}=0.172moles$

Moles of Oxygen = $\frac{\text{Given mass of oxygen}}{\text{Molar mass of oxygen}}=\frac{0.214g}{16g/mole}=0.0133moles$

Step 2: Calculating the mole ratio of the given elements.

For the mole ratio, we divide each value of the moles by the smallest number of moles calculated which is $0.0133$ moles.

For Carbon = $\frac{0.126}{0.0133}=9.5$

For Hydrogen = $\frac{0.172}{0.0133}=12.9\approx 13$

For Oxygen = $\frac{0.0133}{0.0133}=1$

Step 3: Taking the mole ratio as their subscripts.

The ratio of C : H : O = 9.5 : 13 : 1

To make in a whole number we are multiplying the ratio by 2, we get:

The ratio of C : H : O = 19 : 26 : 2

Thus, the empirical formula for the given compound is $C_{19}H_{26}O_2$

The empirical formula weight of $C_{19}H_{26}O_2$ = 19(12) + 26(1) + 2(16) = 286 gram/eq

Now we have to calculate the molecular formula of the compound.

Formula used :

$n=\frac{\text{Molecular formula}}{\text{Empirical formula weight}}$

$n=\frac{286.4}{286}=1$

Molecular formula = $C_{19}H_{26}O_2$

Therefore, the molecular formula for androstenedione is, $C_{19}H_{26}O_2$

3 0

3 years ago