All categories

3 years ago

Please help as soon as possible

Chemistry

1 answer:

polet [3.4K]3 years ago

6 0

Answer:

A. 2.4 x 10¹⁴ J

Explanation:

m (mass) = 2.7 x 10⁻³ kg

c = 3.0 x 10⁸ m/s

Plug these numbers into the equation E=mc²

E=mc²

E= (2.7 x 10⁻³)(3.0 x 10⁸)²

E= 2.43 x 10¹⁴

So, the answer is A. 2.4 x 10¹⁴ J.

You might be interested in

A 50/50 blend of engine coolant and water (by volume) is usually used in an automobile's engine cooling system. If a car's cooli

Diano4ka-milaya [45]

Answer:

$\large \boxed{109.17 \, ^{\circ}\text{C}}$

Explanation:

Data:

50/50 ethylene glycol (EG):water

V = 4.70 gal

ρ(EG) = 1.11 g/mL

ρ(water) = 0.988 g/mL

Calculations:

The formula for the boiling point elevation ΔTb is

$\Delta T_{b} = iK_{b}b$

i is the van’t Hoff factor — the number of moles of particles you get from 1 mol of solute. For EG, i = 1.

1. Moles of EG

$\rm n = 0.50 \times \text{4.70 gal} \times \dfrac{\text{3.785 L}}{\text{1 gal}} \times \dfrac{\text{1000 mL}}{\text{1 L}} \times \dfrac{\text{1.11 g}}{\text{1 mL}} \times \dfrac{\text{1 mol}}{\text{62.07 g}} = \text{159 mol}$

2. Kilograms of water

$m = 0.50 \times \text{4.70 gal} \times \dfrac{\text{3.785 L}}{\text{1 gal}} \times \dfrac{\text{998 g}}{\text{1 L}} \times \dfrac{\text{1 kg}}{\text{1000 g}} = \text{8.88 kg}$

3. Molal concentration of EG

$b = \dfrac{\text{159 mol}}{\text{8.88 kg}} = \text{17.9 mol/kg}$

4. Increase in boiling point

$\rm \Delta T_{b} = iK_{b}b = 1 \times 0.512 \, \, ^{\circ}\text{C} \cdot kg \cdot mol^{-1} \, \times 17.9 \cdot mol \cdot kg^{-1} = 9.17 \, ^{\circ}\text{C}$

5. Boiling point

$\rm T_{b} = T_{b}^{\circ} + \Delta T_{b} = 100.00 \, ^{\circ}\text{C} + 9.17 \, ^{\circ}\text{C} = \mathbf{109.17 \, ^{\circ}C}\\\rm \text{The boiling point of the solution is $\large \boxed{\mathbf{109.17 \, ^{\circ}C}}$}$

7 0

3 years ago

What does the number next to ions signify?

dusya [7]

<span>The number next to the simbol of the element ions (as a superscript) means the number of charges of the ion. For example N (+),, where (+) is a superscript means that the charge of the ion is 1+. S(2-), where (2-) is a superscript, means that the charge of the ion is (2-). OH (-), where (-) is a superscript, means that the charge of OH ion is (1-) . </span>

6 0

3 years ago

Balanced equation for solid magnesium oxide

Y_Kistochka [10]

Answer:

Mg + O2 → MgO

Explanation:

3 0

3 years ago

Forrest spills some acid on the lab floor. He notifies his teacher and begins to look for baking soda to neturalize the acid on

gregori [183]

His classmates should be notified next