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3 years ago

Examine the unbalanced equation.

Chemistry

2 answers:

vlada-n [284]3 years ago

6 0

Answer:

The correct answer is:

4 Al + 3 O₂ → 2 Al₂O₃

Explanation:

The law of conservation of matter states that since no atom can be created or destroyed in a chemical reaction, the number of atoms that are present in the reagents has to be equal to the number of atoms present in the products.

Then, you must balance the chemical equation to comply with the previous law. For that, you must first look at the subscripts next to each atom to find the number of atoms in the equation. If the same atom appears in more than one molecule, you must add its amounts . In this case:

Left side: 2 aluminum and 2 oxygen.

Right side: 2 aluminum and 3 oxygen.

The coefficients located in front of each molecule indicate the amount of each molecule for the reaction. This coefficient can be modified to balance the equation, just as you should never alter the subscripts.

By multiplying the coefficient mentioned by the subscript, you get the amount of each element present in the reaction.

First of all, it is convenient to start balancing the oxygen. In this case you can see that you have 2 on the left side and 3 on the right side. A simple way to balance the oxygen then is to exchange these numbers sideways, placing them as coefficients in front of each molecule that corresponds. Then you get:

___Al + 3 O₂ → 2 Al₂O₃

Now you have:

Left side: 2 aluminum and 6 (3*2) oxygen.

Right side: 4 (2*2) aluminum and 6 (3*2) oxygen.

Now that the oxygen is balanced, you balance the aluminum as follows:

4 Al + 3 O₂ → 2 Al₂O₃

Now you have:

Left side: 4 aluminum and 6 oxygen.

Right side: 4 (2*2) aluminum and 6 oxygen.

Since you have the same amount of each element on each side of the equation, the equation is balanced.

So the correct answer is:

4 Al + 3 O₂ → 2 Al₂O₃

IceJOKER [234]3 years ago

3 0

___Al + ___O2 → ___Al2O3

4Al + 3O2 → 2Al2O3

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How many moles of potassium oxide (K2O) will be formed when 1.52 moles of potassium reacts with oxygen according to the followin

Ghella [55]

The balanced chemical reaction is given above however I believe the coefficients are wrong. It should be:

4K + O2 = 2K2O

We use data from that reaction to obtain relationships between substances. We are given the amount of potassium that reacts. We proceed as follows:

1.52 mol K ( 2 mol K2O / 4 mol K ) = 0.76 mol of K2O is formed

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4 years ago

Sarah measures out 151 grams of SO2. How many miles is this? Express your answer to three significant figures

elena-s [515]

150 g SO₂ = 2.36 mol SO₂

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3 years ago

Use the information in the table about four different electric circuits to answer the question

ycow [4]

Answer:

Circuit 4

Explanation:

To know the correct answer to the question given above, we shall determine the current in each circuit. This can be obtained as follow:

For circuit 1:

Resistance (R) = 0.5 ohms

Voltage (V) = 20 V

Current (I) =?

V = IR

20 = I × 0.5

Divide both side by 0.5

I = 20 / 0.5

I = 40 A

For circuit 2:

Resistance (R) = 0.5 ohms

Voltage (V) = 40 V

Current (I) =?

V = IR

40 = I × 0.5

Divide both side by 0.5

I = 40 / 0.5

I = 80 A

For circuit 3:

Resistance (R) = 0.25 ohms

Voltage (V) = 40 V

Current (I) =?

V = IR

40 = I × 0.25

Divide both side by 0.25

I = 40 / 0.25

I = 160 A

For circuit 4:

Resistance (R) = 0.25 ohms

Voltage (V) = 60 V

Current (I) =?

V = IR

60 = I × 0.25

Divide both side by 0.25

I = 60 / 0.25

I = 240 A

SUMMARY

Circuit >>>>>> Current

1 >>>>>>>>>>> 40 A

2 >>>>>>>>>>> 80 A

3 >>>>>>>>>>> 160 A

4 >>>>>>>>>>> 240 A

From the above calculation, circuit 4 has the greatest electric current.

8 0

3 years ago

(CH3)2-CH-CH2-O(CH3)3IUPAC NAME

bazaltina [42]

Answer:

1-(tert-butoxy)-2-methylpropane

Note: there is a mistake in formula, the correct formula is (CH₃)₂-CH-CH₂-O-C(CH₃)₃ not (CH₃)₂-CH-CH₂-O(CH₃)₃, because oxygen is a divalent compound.

Explanation:

Structural formula is attached

IUPAC naming rules

1. start numbering the chain from the functional group. In this compound we start from oxygen side.

2. Here we can see that at position 1 there is an oxy group along with a tertiary carbon having three methyl groups. So we write it as 1-tert-butoxy. Which means that there is a methoxy group at position 1 along with a tertiary carbon.

3. At position 2 we can see that there is a methyl group attached to the main chain, so we write it as 2-methyl.

4. Now we count the total number of carbons in the main chain. As we can see that there are 3 carbons in the remaining or parent chain, so we write it as propane

5. So the IUPAC name of the compound will be 1-(tert-butoxy)-2-methylpropane

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4 years ago

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Anton [14]

The fluoride content of bottled water is unpredictable.

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