3) 2500 pounds to Kilograms Would this be 1,250?

What quantity of copper is deposited by the same quantity of electricity that deposited 9g of aluminum

klio [65]

Answer:

Mass of copper deposited = 31.75 g

Explanation:

According to Faraday's second law of electrolysis, when the same quantity of electricity is passed through different electrolytes, the relative number of moles of the elements deposited are inversely proportional to the charges on the ions of the elements.

From this law, it can be seen that the higher the charge, the lower the number of moles of a given element deposited.

Number of moles of aluminium in 9 g of aluminium = mass / molar mass

Molar mass of aluminium = 27 g

Number of moles of aluminium = 9/27 = 1/3 moles

Charge on aluminium ion = +3

3 moles of electrons will discharge 1 mole of aluminium,

1 mole of electrons will discharge 1/3 moles of aluminium

Number of moles of electrons involved = 1 mole of electrons

Charge on copper ion = +2

1 mole of electrons will discharge 1/2 moles of copper.

Mass of 1/2 moles of copper = number of moles × molar mass of copper

Molar mass of copper = 63.5 g

Mass of copper deposited = 1/2 × 63.5 = 31.75 g

3 0

3 years ago

Alex wants to find out if different amounts of water affect plant growth. She waters three bean plants with three different amou

rosijanka [135]

The answer is C. The height of the plants.

3 0

2 years ago

What mass of zinc is needed to react with 23.1 g of phrosphoric acid according tot he equation?

Hitman42 [59]

Complete Question:

what mass of zinc is needed to react with 23.1 g of phosphoric acid according tot he equation?

3 Zn + 2 H₃PO₄ = 3 H₂ + Zn₃(PO₄)₂

Answer:

22.98 g, the mass of zinc (Zn) is needed to react with 23.1 g of phosphoric acid according to the given equation.

Explanation:

Given chemical reaction:

3 Zn + 2 H₃PO₄ = 3 H₂ + Zn₃(PO₄)₂

If the substance’ molecular weight is the number of grams required per mole, the number of moles expressed as a given quantity of substances shall correspond to the grams of that substance divided by the molecular weight. Hence,

$\text {number of moles}=\frac{\text {mass}}{\text {molar weight}}$

To find no. of moles of phosphoric acid:

Given:

mass of phosphoric acid = 23.1 g

molar weight of of phosphoric acid = 97.994 = 98 g/mole

Therefore,

no. of moles of phosphoric acid $=\frac{23.1}{98}=0.2357 \text { moles }$

Look into the given chemical reaction and divide as the following:

If 2 moles of H₃PO₄ reacts with 3 moles of Zn then 0.2357 moles of H₃PO₄ reacts with X moles of Zn. Then,

$\text { X moles of } \mathrm{Zn}=\frac{(0.2357 \times 3)}{2}=\frac{0.707}{2}=0.3535 \text { moles of } \mathrm{Zn}$

Now, calculate mass of zinc as follows, we know

molar mass of zinc is 65 g/mol

$mass\ of\ zinc = number\ of\ moles \times molar\ weight =0.3535 \times 65$

Mass of zinc = 22.98 g

7 0

3 years ago

Which word describes the water stored below Earth's surface?

DiKsa [7]

Answer:

I believe it is ground water

5 0

3 years ago

Read 2 more answers

3. Round each measurement to three significant figures. Write your

Mekhanik [1.2K]

In scientific notation, the measurement of each figure to three significant measurements are as follows:

87.073 meters = 8.71 × 10⁻¹ meters
4.3621 × 10⁸ meters = 4.36 × 10⁸ meters
0.01552 meter = 1.55 × 10² meters
9009 meters = 9.01 × 10² meters
1.7777 x 10-3 m = 1.78 × 10⁻³ meters
629.55 meters = 6.30 × 10² meters

A significant figure is the digits in a number that is dependable and absolutely essential to express the quantity of a figure in positional notation. They are utilized to represent the appropriate degree of precision.

A scientific notation is used to express a large number in an easy decimal way multiplied by its power of 10.

From the given information, in scientific notation, and to three significant figures, we have:

87.073 meters = 8.71 × 10⁻¹ meters
4.3621 × 10⁸ meters = 4.36 × 10⁸ meters
0.01552 meter = 1.55 × 10² meters
9009 meters = 9.01 × 10² meters
1.7777 x 10-3 m = 1.78 × 10⁻³ meters
629.55 meters = 6.30 × 10² meters

Therefore, from the above concept, we can conclude that the scientific notation of each figure in three significant figures is shown in bold format.

Learn more about scientific notation here:

brainly.com/question/1705769?referrer=searchResults

4 0

2 years ago