The valence of aluminum is +3, and the valence of chlorine is –1. The formula for aluminum chloride is correctly written as

The low-grade iron ore taconite, which contains Fe3O4, is concentrated and made into pellets for processing. If one ton of tacon

xenn [34]

<u>Answer:</u> The percent composition of $Fe_3O_4$ in taconite is 37.6 %.

<u>Explanation:</u>

We are given:

Mass of taconite pellets = 1 ton = 907185 g (Conversion factor: 1 ton = 907185 g)

Mass of iron produced = 545 lb = 247212 g (Conversion factor: 1 lb = 453.6 g )

We know that:

Molar mass of iron = 55.85 g/mol

Molar mass of $Fe_3O_4$ = 231.53 g/mol

1 mole of $Fe_3O_4$ contains 3 moles of iron atom and 4 moles of oxygen atom

(3 × 55.85) = 167.55 g of iron is produced from 231.53 grams of $Fe_3O_4$

So, 247212 grams of iron will be produced from = $\frac{231.53}{167.55}\times 247212=341611.43g$ of $Fe_3O_4$

To calculate the percentage of $Fe_3O_4$ in taconite, we use the equation:

$\%\text{ composition of }Fe_3O_4=\frac{\text{Mass of }Fe_3O_4}{\text{Mass of taconite}}\times 100$

Mass of taconite = 907185 g

Mass of $Fe_3O_4$ = 341611.43 g

Putting values in above equation, we get:

$\%\text{ composition of }Fe_3O_4=\frac{341611.43g}{907185g}\times 100=37.6\%$

Hence, the percent composition of $Fe_3O_4$ in taconite is 37.6 %.

8 0

3 years ago

Help me pls

harkovskaia [24]

Answer:

this is answers to the second picture

Explanation:

1- energy

2- structure

3- reaction

4- substance

5- reactants

6- products

7- changed

8- At first there is no reaction because of the protective oxide coating on the aluminum. But soon an exothermic reaction between bromine and aluminum causes brown fumes of bromine to be given off. But as a new substance, aluminum bromide is produced. White smoke is produced.

9- heated to 120 degrees Celsius it melts and first forms a pale-yellow liquid.

In this form the atoms are covalently bonded, and the liquid can flow easily. However, heated up beyond 150 degrees Celsius, the result is a dark red

10- When a chemical change occurs it is more difficult to revert the substance back to its original state. (To be honest I don't know)

3 0

2 years ago

calculate the mass of 120cc nitrogen present at STP. how many number of molecules are present in it?

Stells [14]

Answer:

$0.15008\ \text{g}$

$3.23\times 10^{21}$

Explanation:

1 mol of nitrogen at STP = 22.4 L = 22400 cc

n = Mol of $N_2$ = $\dfrac{120}{22400}=0.00536\ \text{mol}$

M = Molar mass of $N_2$ = $28\ \text{g/mol}$

$N_A$ = Avogadro's number = $6.022\times 10^{23}\ \text{mol}^{-1}$

Mass of $N_2$ is

$m=nM\\\Rightarrow m=0.00536\times 28\\\Rightarrow m=0.15008\ \text{g}$

Mass of the nitrogen is $0.15008\ \text{g}$

Number of molecules is given by

$nN_A=0.00536\times 6.022\times 10^{23}=3.23\times 10^{21}\ \text{molecules}$

The number of molecules present in it are $3.23\times 10^{21}$

5 0

3 years ago

5g of aspirin will powder will take effect more quickly than a 5g aspirin tablet because the powder has more what

Pani-rosa [81]

Answer:

Explanation:

Because the powder has more finer and larger surface area hence it absorbed faster and it becomes more effective in performance compared to the tablet that will still need to be dissolved before it is been assimilated into the body system.

7 0

3 years ago

What is the most likely reason that nonmetals are electrical insulators?

Ray Of Light [21]

Answer:

Since valence shells are mostly empty in nonmetal atoms, the atoms attract and hold any electrons they can in order to fill their valence shells.

6 0

3 years ago