Which two planets have the same density ?

How much energy is released by the decay of 3 grams of 230Th in the following reaction 230 Th - 226Ra + "He (230 Th = 229.9837 g

Serhud [2]

Answer: The energy released for the decay of 3 grams of 230-Thorium is $2.728\times 10^{-15}J$

Explanation:

First we have to calculate the mass defect $(\Delta m)$ .

The equation for the alpha decay of thorium nucleus follows:

$_{90}^{230}\textrm{Th}\rightarrow _{88}^{226}\textrm{Ra}+_2^{4}\textrm{He}$

To calculate the mass defect, we use the equation:

Mass defect = Sum of mass of product - Sum of mass of reactant

$\Delta m=(m_{Ra}+m_{He})-(m_{Th})$

$\Delta m=(225.9771+4.008)-(229.9837)=1.4\times 10^{-3}amu=2.324\times 10^{-30}kg$

(Conversion factor: $1amu=1.66\times 10^{-27}kg$ )

To calculate the energy released, we use Einstein equation, which is:

$E=\Delta mc^2$

$E=(2.324\times 10^{-30}kg)\times (3\times 10^8m/s)^2$

$E=2.0916\times 10^{-13}J$

The energy released for 230 grams of decay of thorium is $2.0916\times 10^{-13}J$

We need to calculate the energy released for the decay of 3 grams of thorium. By applying unitary method, we get:

As, 230 grams of Th release energy of = $2.0916\times 10^{-13}J$

Then, 3 grams of Th will release energy of = $\frac{2.0916\times 10^{-13}}{230}\times 3=2.728\times 10^{-15}J$

Hence, the energy released for the decay of 3 grams of 230-Thorium is $2.728\times 10^{-15}J$

5 0

2 years ago

Silver nitrate solution reacts with calcium chloride solution according to the equation: 2 AgNO3 + CaCl2 → Ca(NO3)2 + 2 AgCl All

HACTEHA [7]

Answer:

14.33 g

Explanation:

Solve this problem based on the stoichiometry of the reaction.

To do that we need the molecular weight of the masses involved and then calculate the number of moles, find the limiting reagent and finally calculate the mass of AgCl.

2 AgNO₃ + CaCl₂ ⇒ Ca(NO₃)₂ + 2 AgCl

mass, g 6.97 6.39 ?

MW ,g/mol 169.87 110.98 143.32

mol =m/MW 0.10 0.06 0.10

From the table above AgNO₃ is the limiting reagent and we will produce 0.10 mol AgCl which is a mass :

0.10 mol x 143.32 g/mol = 14.33 g

5 0

3 years ago

Which is the metric standard for measuring energy? Which unit is used for specific heat capacity? If you wanted to compare the a

DENIUS [597]

1. Which is the metric standard for measuring energy?

The metric standard for measuring of energy defined by the International System of Units is the joule (J), which is defined as the work done by a force of a newton in a displacement of one meter in the direction of force. So,

1 J = 1 N m = 1 kg·m²/s²

Calorie is also frequently used in scientific and technological applications. Calorie is a unit of thermal energy that is equivalent to the amount of heat needed to raise the temperature of 1 gram of water by 1 degree Celsius.

1 cal = 4,184 J

2. Which unit is used for specific heat capacity?

The specific heat capacity (c) is a physical quantity that is defined as the amount of heat (q) that must be supplied to the mass unit of a thermodynamic substance or system to raise its temperature by one unit. So,

c = q / m ΔT

where m is the mass of the substance and ΔT is the temperature increase.

In this way, as heat is a form of energy, the International System of Units expresses the specific heat in joules per kilogram and per kelvin (J kg⁻¹ K⁻¹). Another common unit, not belonging to the SI, is the calorie per gram and per degree centigrade (cal g⁻¹ ° C⁻¹).

3. If you wanted to compare the abilities of olive oil and peanut oil to gain or lose thermal energy, which unit would you use?

You should use units of specific heat capacity (J kg⁻¹ K⁻¹) since, as mentioned above, this is a physical quantity that measures the amount of heat that must be supplied to an specific mass of a substance or system to raise its temperature.

Heat is a thermal energy, so by using heat capacity units you can compare the ability of olive oil and peanut oil to gain or lose thermal energy by varying its temperature.

3 0

3 years ago

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Sunlight, when viewed through a prism or a diffraction grating, shows all of the colors of visible light. This is an example of

nata0808 [166]

A spectrum that includes all colors and doesn't have
any gaps in it is a continuous spectrum.

8 0

3 years ago

Why are polar bears listed as a threatened species?

IceJOKER [234]

Because their species is in danger of going extinct

5 0

3 years ago

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