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3 years ago

8

Type the correct answer in each box. In an atom, the first energy level can hold electrons. The second energy level can hold ele

ctrons. The third energy level can hold electrons.

1 answer:

Elis [28]3 years ago

4 0

I might be wrong but I think its 2 then 4 then 8

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What would happen if you added more than 5ml of H2O2 to the 5ml of yeast

anzhelika [568]

Hydrogen peroxide breaks down into water and oxygen.

2H₂O₂ → 2H₂O + O₂

The yeast present contains an enzyme called catalase which catalyses the reaction.

More the amount of the catalyst added, faster will be the decomposition of the hydrogen peroxide.

Thus if we added more than 5 mL of yeast solution to the 2H₂O₂, the breakdown would occur faster. Thus the bubbles and the accompanying fizz would be much more.

Read more on Brainly.com - brainly.com/question/10670134#readmore

7 0

3 years ago

Read 2 more answers

In the equation below

yulyashka [42]

Answer:

6.25 moles of N₂ is produced, and 18.8 moles of Cu and H₂O is produced.

Explanation:

We are given the chemical equation:

$\displaystyle 2\text{NH$_3$}_\text{(g)} + 3\text{CuO}_\text{(s)} \longrightarrow \text{N$_2$}_\text{(g)} + 3\text{Cu}_\text{(s)}+3\text{H$_2$O}_\text{(g)}$

And we want to determine the amount of products produced when 12.5 moles of NH₃ is reacted with excess CuO.

Compute using stoichiometry. From the equation, we can see the following stoichiometric ratios:

The ratio between NH₃ and N₂ is 2:1. (i.e. One mole of N₂ is produced from every two moles of NH₃.)

The ratio between NH₃ and Cu is 2:3.
The ratio between NH₃ and H₂O is 2:3. (i.e. Three moles of H₂O or Cu is produced frome every two moles of NH₃.)

Dimensional Analysis:

The amount of N₂ produced:

$\displaystyle 12.5\text{ mol NH$_3$} \cdot \frac{1\text{ mol N$_2$}}{2\text{ mol NH$_3$}} = 6.25\text{ mol N$_2$}$

The amount of Cu produced:

$\displaystyle 12.5\text{ mol NH$_3$} \cdot \frac{3\text{ mol Cu}}{2\text{ mol NH$_3$}} = 18.8\text{ mol Cu}$

And the amount of H₂O produced:

$\displaystyle 12.5\text{ mol NH$_3$} \cdot \frac{3\text{ mol H$_2$O}}{2\text{ mol NH$_3$}} = 18.8\text{ mol H$_2$O}$

In conclusion, 6.25 moles of N₂ is produced, and 18.8 moles of Cu and H₂O is produced.

8 0

2 years ago

Teeth and long bones are good indicators of age in children; ribs and joints are better for adults.

attashe74 [19]

Answer:

True

Explanation:

7 0

3 years ago

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Ammonium nitrate is an ingredient in cold packs used by sports trainers for injured athletes. Calculate the change in temperatur

Ronch [10]

Answer:

See explanation

Explanation:

First, we need to use the correct expression:

Q = m*Cp*ΔT (1)

Q = n*ΔH (2)

These are the 2 expressions to calculate heat or energy.

Now, we want to know the change of temperature of the nitrate in water after being added, so with the innitial data of nitrate, we can calculate heat using the second expression. First, we need to calculate moles with the molecular mass:

n = m/MM

n = 42/80.1 = 0.52 moles

With these moles, we can calculate heat with the ΔH of this reaction:

Q = 0.52 * 25.7 = 13.364 kJ or 13,364 J

However, this heat as is being absorbed, the value would be negative.

Now that we have heat, we can use expression (1) and plug these values to solve for ΔT, but before, we need to know the total mass of the solution (water + nitrate)

m = 250 + 42 = 292 g

now, solving for ΔT:

-13,364 = 292 * 4.18 * ΔT

ΔT = -13,363 / (292 * 4.18)

ΔT = -10.95 °C

3 0

3 years ago

Where is desertification likely to occur?

viktelen [127]

I think in drylands, drylands are particularly affected by desertification.

5 0

4 years ago

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