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3 years ago

An atom is described as a nucleus of protons and neutrons surrounded by a

Chemistry

2 answers:

Vlad1618 [11]3 years ago

6 0

Answer:

Explanation:

The nucleus (center) of the atom contains the protons (positively charged) and the neutrons (no charge). The outermost regions of the atom are called electron shells and contain the electrons (negatively charged). Atoms have different properties based on the arrangement and number of their basic particles.

zheka24 [161]3 years ago

6 0

An atom is described as a nucleus of protons and neurons surrounded by a negatively charged particle(s) called electron.

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What is the volume of 15.2 grams of SO2 at STP?

kiruha [24]

5.512 litres is the volume of 15.2 grams of sulphur dioxide gas at STP.

Explanation:

Data given:

mass of sulphur dioxide = 15.2 grams

conditions is at STP whech means volume = 22.4 litres

atomic mass of sulphur dioxide = 64.06 grams/mole

Number of moles is calculated as:

number of moles = $\frac{mas}{atomic mass of 1 mole}$

Putting the values in the equation:

number of moles = $\frac{15.2}{64.06}$

= 0.23 moles

Assuming that sulphur dioxide behaves as an ideal gas, we can calculate the volume as:

When 1 mole of sulphur dioxide occupies 22.4 litres at STP

Then 0.23 moles of sulphur dioxide occupies 22.4 x 0.23

= 5.152 litres is the volume.

5 0

3 years ago

In an aqueous solution, 42% of a substance dissociates to release hydronium ions. Which of the following statements is true for

const2013 [10]

Answer: The statement it is a weak acid is true for the substance.

Explanation:

An acid that dissociates completely when dissolved in water to give hydrogen $(H^{+})$ or hydronium $(H_{3}O^{+})$ ions is called a strong acid.

For example, HCl is a strong acid.

$HCl + H_{2}O \rightarrow H_{3}O^{+} + Cl^{-}$

An acid that dissociates partially or weakly when dissolved in water to given hydrogen or hydronium ions is called a weak acid.

For example, $CH_{3}COOH$ is a weak acid.

$CH_{3}COOH \rightleftharpoons CH_{3}COO^{-} + H_{3}O^{+}$

A strong base is a base which when dissolved in water then it dissociates completely to give hydroxide ions.

For example, NaOH is a strong acid.

A weak base is a base which when dissolved in water then it dissociates partially or weakly to give hydroxide ions.

For example, $NH_{3}$ is a weak base.

Hence, in an aqueous solution where 42% of a substance dissociates to release hydronium ions shows that the dissociation is less than 50%. This means that substance is dissociating weakly so, it is a weak acid.

Thus, we can conclude that the statement it is a weak acid is true for the substance.

5 0

2 years ago

Which substance can not be decomposed by a chemical change? (1) AlCl3 (3) HI (2) H2O (4) Cu

user100 [1]

Cooper is the substance that can't be decomposed by a chemical chAnge. So 4)

5 0

3 years ago

Read 2 more answers

Determine the limiting reactant (lr) and the mass (in g) of nitrogen that can be formed from 50.0 g n2o4 and 45.0 g n2h4. some p

Licemer1 [7]

N2O4(l) + 2 N2H4(l) → 3 N2(g) + 4 H2O(g)
1) to calculate the limiting reactant you need to pass grams to moles.
 moles is calculated by dividing mass by molar mass

mass of N2O4: 50.0 g
molar mass of N2O4 = 92.02 g/mol
molar mass of N2H4 = 32.05 g/mol.
mass of N2H4:45.0 g

moles N2O4=50.0/92.02 g/mol= 0,54 mol of N2O4
moles N2H4= 45/32.05 g/mol= 1,40 mol of N2H4

 2)
By looking at the balanced equation, you can see that 1 mol of N2O4 needs 2 moles of N2H4 to fully react . So to react 0,54 moles of N2O4, you need 2x0,54 moles of N2H4 moles
N2H4 needed = 1,08 moles.
You have more that 1,08 moles N2H4, so this means the limiting reagent is not N2H4, it's N2O4. The molecule that has molecules that are left is never the limiting reactant.

3) 1 mol of N2O4 reacting, will produce 3 mol of N2 (look at the equation)
There are 0,54 mol of N2O4 available to react, so how many moles will produce of N2?
1 mol N2O4------------3 mol of N2
0,54 mol N2O4--------x
x=1,62 mol of N2

4) the only thing left to do is convert the moles obtained, to grams.
We use the same formula as before, moles equal to mass divided by molar mass.
$moles= \frac{grams}{molar mass}$ (molar mass of N2= 28)
1,62 mol of N2= mass/ 28
mass of N2= 45,36 grams

4 0

3 years ago

Which process in the light-dependent reactions results in the release of hydrogen ions, electrons, and oxygen?

vodomira [7]

The high-energy electron travels down an electron transport chain, losing energy as it goes.
Some of the released energy drives pumping of \text H^+H+H, start superscript, plus, end superscript ions from the stroma into the thylakoid interior, building a gradient.
H^+H+H, start superscript, plus, end superscript ions from the splitting of water also add to the gradient.
 H^+H+H, start superscript, plus, end superscript ions flow down their gradient and into the stroma, they pass through ATP synthase, driving ATP production in a process known as chemiosmosis.

3 0

3 years ago

Read 2 more answers