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2 years ago

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Chemistry

1 answer:

mamaluj [8]2 years ago

4 0

Answer:

1. molecule, cell, tissue, organ, organ system, organism, population, community, ecosystem, biosphere

2. A

3. D

4. C

5. C

6. C

7. C

8. B

9. Sorry I don't know :(

10. B

11. A

12. C

13. Sorry :((

14. C

15. a

16. d

Sorry I don't know the rest.. I hope this helps though!!

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Please help me if your good with science:).

stellarik [79]

D an average train goes 300 km/h or 190-220 mph

5 0

3 years ago

Suppose of copper(II) acetate is dissolved in of a aqueous solution of sodium chromate. Calculate the final molarity of acetate

uranmaximum [27]

Answer:

0.0714 M for the given variables

Explanation:

The question is missing some data, but one of the original questions regarding this problem provides the following data:

Mass of copper(II) acetate: $m_{(AcO)_2Cu} = 0.972 g$

Volume of the sodium chromate solution: $V_{Na_2CrO_4} = 150.0 mL$

Molarity of the sodium chromate solution: $c_{Na_2CrO_4} = 0.0400 M$

Now, when copper(II) acetate reacts with sodium chromate, an insoluble copper(II) chromate is formed:

$(CH_3COO)_2Cu (aq) + Na_2CrO_4 (aq)\rightarrow 2 CH_3COONa (aq) + CuCrO_4 (s)$

Find moles of each reactant. or copper(II) acetate, divide its mass by the molar mass:

$n_{(AcO)_2Cu} = \frac{0.972 g}{181.63 g/mol} = 0.0053515 mol$

Moles of the sodium chromate solution would be found by multiplying its volume by molarity:

$n_{Na_2CrO_4} = 0.0400 M\cdot 0.1500 L = 0.00600 mol$

Find the limiting reactant. Notice that stoichiometry of this reaction is 1 : 1, so we can compare moles directly. Moles of copper(II) acetate are lower than moles of sodium chromate, so copper(II) acetate is our limiting reactant.

Write the net ionic equation for this reaction:

$Cu^{2+} (aq) + CrO_4^{2-} (aq)\rightarrow CuCrO_4 (s)$

Notice that acetate is the ion spectator. This means it doesn't react, its moles throughout reaction stay the same. We started with:

$n_{(AcO)_2Cu} = 0.0053515 mol$

According to stoichiometry, 1 unit of copper(II) acetate has 2 units of acetate, so moles of acetate are equal to:

$n_{AcO^-} = 2\cdot 0.0053515 mol = 0.010703 mol$

The total volume of this solution doesn't change, so dividing moles of acetate by this volume will yield the molarity of acetate:

$c_{AcO^-} = \frac{0.010703 mol}{0.1500 L} = 0.0714 M$

8 0

4 years ago

If you have a 150-gram sample of CrO3: • How many moles of CrO3 do you have? • How many oxygen atoms do you have? • How many gra

docker41 [41]

Answer :

(a) The moles of $CrO_3$ is, 1.5 moles.

(b) The number of oxygen atoms are, $27.099\times 10^{23}$

(c) The mass of oxygen is, 72 grams.

Explanation : Given,

Mass of $CrO_3$ = 150 g

Molar mass of $CrO_3$ = 100 g/mole

Molar mass of oxygen = 16 g/mole

(a) First we have to calculate the moles of $CrO_3$ .

$\text{Moles of }CrO_3=\frac{\text{Mass of }CrO_3}{\text{Molar mass of }CrO_3}=\frac{150g}{100g/mole}=1.5moles$

The moles of $CrO_3$ is, 1.5 moles.

(b) Now we have to calculate the number of oxygen atoms.

In $CrO_3$ , there are 1 atom of chromium and 3 atoms of oxygen.

According to the mole concept,

1 mole of $CrO_3$ contains $3\times 6.022\times 10^{23}$ number of oxygen atoms.

So, 1.5 mole of $CrO_3$ contains $1.5\times 3\times 6.022\times 10^{23}=27.099\times 10^{23}$ number of oxygen atoms.

The number of oxygen atoms are, $27.099\times 10^{23}$

(c) Now we have to calculate the mass of oxygen.

As, 1 mole of $CrO_3$ contains 3 moles of oxygen

So, 1.5 mole of $CrO_3$ contains $1.5\times 3=4.5$ moles of oxygen

$\text{Mass of oxygen}=\text{Moles of oxygen}\times \text{Molar mass of oxygen}$

$\text{Mass of oxygen}=(4.5mole)\times (16g/mole)=72g$

The mass of oxygen is, 72 grams.

3 0

3 years ago

In what type of reaction will an acid and a base react with each other

Arada [10]

When an acid and a base are placed together, they react to neutralize the acid and base properties, producing a salt. The H(+) cation of the acidcombines with the OH(-) anion of the base to form water.

6 0

3 years ago

Read 2 more answers

What are the conditions to liquefy a gas ?

kykrilka [37]

Decreasing temperature and increasing pressure

5 0

3 years ago

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