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2 years ago

With reference to He-4 (or the diagram), explain the term isotopes.

Chemistry

1 answer:

boyakko [2]2 years ago

6 0

Answer:

Isotopes are basically atoms of an element that have an unequal number of neutrons and protons. Of course the proton number remains the same, but the neutron number either decreases or increases, which leads to an overall change in mass. However, no chemical properties of the atom/element are changed as the electrons are the same number and do not react. In regards to Helium 4, the original number of neutrons in Helium is 2, and protons 2 as well. We see an equal number of neutrons and protons, hence an unchanged mass, and the element is not an isotope.

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A container has a volume of 2.79 L and a pressure of 5.97 atm. If the pressure changes to 1460 mm Hg, what is the container’s ne

maw [93]

Answer:

8.68 L is the new volume

Explanation:

You use Boyle's law for this.

$P_{1}V_{1}=P_{2}V_{2}$

$P_{1}$ = first pressure

$P_{2}$ = second pressure

$V_{1}$ = first volume

$V_{2}$ = second volume

Convert pressure from atm to mmHg (use same units):

5.97 x 760 = 4537.2 -> 4.54 x 10³

...maintain 3 significant figures in calculation, and round as needed...

(4.54 x 10³ mmHg)(2.79 L) = (1460 mmHg)( $V_{2}$ )

(4.54 x 10³ mmHg)(2.79 L) / (1460 mmHg) = $V_{2}$ = 8.68 L

Hope this helps :)

5 0

2 years ago

Use the periodic table to answer this question. Decomposing calcium carbonate yields calcium oxide and carbon dioxide. What info

Anuta_ua [19.1K]

Atomic number and place on table.

8 0

3 years ago

Read 2 more answers

How many grams of Sg is required to produce 83.10 g SF6? S: +24F-->8SF

ozzi

Answer : The mass of $S_8$ required is 18.238 grams.

Explanation : Given,

Mass of $SF_6$ = 83.10 g

Molar mass of $SF_6$ = 146 g/mole

Molar mass of $S_8$ = 256.52 g/mole

The balanced chemical reaction is,

$S_8+24F_2\rightarrow 8SF_6$

First we have to determine the moles of $SF_6$ .

$\text{Moles of }SF_6=\frac{\text{Mass of }SF_6}{\text{Molar mass of }SF_6}=\frac{83.10g}{146g/mole}=0.569moles$

Now we have to determine the moles of $S_8$ .

From the balanced chemical reaction we conclude that,

As, 8 moles of $SF_6$ produced from 1 mole of $S_8$

So, 0.569 moles of $SF_6$ produced from $\frac{0.569}{8}=0.0711$ mole of $S_8$

Now we have to determine the mass of $S_8$ .

$\text{Mass of }S_8=\text{Moles of }S_8\times \text{Molar mass of }S_8$

$\text{Mass of }S_8=(0.0711mole)\times (256.52g/mole)=18.238g$

Therefore, the mass of $S_8$ required is 18.238 grams.

7 0

3 years ago

2.822 mol of nickel has _________ atoms of nickel. (Enter just the number for this one.)

Irina-Kira [14]

Hello!

To find the number of atoms in 2.822 moles of nickel, we need to multiply it by Avogadro's number. Avogadro's number is 6.02 x 10^23 atoms.

2.822 moles x (6.02 x 10^23) ≈ 1.698844 x 10^24

Therefore, there are about 1.70 x 10^24 atoms (according to the number of significant figures) in 2.822 moles of nickel.

6 0

3 years ago

A large balloon is initially filled to a volume of 25.0 L at 353 K and a pressure of 2575 mm Hg. What volume of gas will the bal

bija089 [108]

Answer:

45.0 L is the volume of gas will the balloon contain at 1.35 atm and 253 K.

Explanation:

Using Ideal gas equation for same mole of gas as

$\frac {{P_1}\times {V_1}}{T_1}=\frac {{P_2}\times {V_2}}{T_2}$

Given ,

V₁ = 25.0 L

V₂ = ?

P₁ = 2575 mm Hg

Also, P (atm) = P (mm Hg) / 760

P₁ = 2575 / 760 atm = 3.39 atm

P₂ = 1.35 atm

T₁ = 353 K

T₂ = 253 K

Using above equation as:

$\frac {{P_1}\times {V_1}}{T_1}=\frac {{P_2}\times {V_2}}{T_2}$

$\frac{{3.39}\times {25.0}}{353}=\frac{{1.35}\times {V_2}}{253}$

$\frac{1.35V_2}{253}=\frac{3.39\times \:25}{353}$

Solving for V₂ , we get:

V₂ = 45.0 L

45.0 L is the volume of gas will the balloon contain at 1.35 atm and 253 K.

4 0

3 years ago