Question 13 (5 points)

arlik [135]

∆H = m x s x ∆T, where m is the mass of the reactants, s is the specific heat of the product, and ∆T is the change in temperature from the reaction.

5 0

2 years ago

How does the mass of an electron compare to the mass of a proton and a

tensa zangetsu [6.8K]

Answer:

C. The mass of an electron is much less than the mass of a proton or

a neutron.

Explanation:

When we compare the mass of an electron to that of proton or neutron, the mass of an electron is much less than the mass of a proton or a neutron.

Electrons are negatively charged particles in an atom

Protons are positively charged particles

Neutrons do not carry any charges.

The relative mass of an electron compared to that of a proton is $\frac{1}{1840}$
This is a very small value
Electrons generally have mass of 9.11 x 10⁻³¹kg
Protons weigh 1.67 x 10⁻²⁷kg

Neutrons weigh 1.68 x 10⁻²⁷kg

We can see that electrons have very small mass and this is why when calculating the mass of an atom, we use the sum of the number of protons and neutrons.

6 0

2 years ago

Which quantity is equivalent to the product of the absolute index of refraction of water and the speed of light in water?

givi [52]

The quantity which is equivalent to the product of the absolute index of refraction of water and the speed of light in water system is the speed of light in vacuum.

<h3>What is the speed of light?</h3>

Speed of light is the rate of speed though the light travels. To find the speed of light in any medium, the following formula is used.

$v=\dfrac{c}{n}$

Here, (n) is the index of reaction and (c) is the speed of light in the vacuum. The speed of light in the vacuum is almost equal to the 3.0×10⁸ m/s.

Now the quantity which is equivalent to the product of the absolute index of refraction of water and the speed of light in water has to be find out.

The above formula can be written as,

$v=\dfrac{c}{n}\\vn=c\\c=vn$

Here, the product of index of refraction and speed of light is equal to the speed of light in vacuum. This will be true for water as well.

Thus, the quantity which is equivalent to the product of the absolute index of refraction of water and the speed of light in water system is the speed of light in vacuum.

Learn more about the speed of light here;

brainly.com/question/104425

#SPJ4

3 0

1 year ago

Describe how to draw a 3-heptyne

lesantik [10]

You can't really describe it but this is what it looks like http://www.chemspider.com/Chemical-Structure.453291.html

3 0

3 years ago

Calculate the percent ionization of formic acid (hco2h) in a solution that is 0.311 m in formic acid and 0.189 m in sodium forma

ohaa [14]

Answer: 0.094%

Explanation:


1) Equilibrium chemical equation:


Only the ionization of the formic acid is the important part.


HCOOH(aq) ⇄ HCOO⁻(aq) + H⁺(aq).


2) Mass balance:


 HCOOH(aq) HCOO⁻(aq) H⁺(aq).

Start 0.311 0.189

Reaction - x +x +x

Final 0.311 - x 0.189 + x x

3) Acid constant equation:


Ka = [HCOO-] [N+] / [HCOOH] = (0.189 + x) x / (0.311 -x)


= (0.189 + x )x / (0.311 - x) = 0.000177

4) Solve the equation:

You can solve it exactly (it will lead to a quadratic equation so you can use the quadratiic formula). I suggest to use the fact that x is much much smaller than 0.189 and 0.311.


With that approximation the equation to solve becomes:

0.1890x / 0.311 = 0.000177, which leads to:

x = 0.000177 x 0.311 / 0.189 = 2.91 x 10⁻⁴ M

5) With that number, the percent of ionization (alfa) is:


percent of ionization = (moles ionized / initial moles) x 100 =


percent ionization = (concentration of ions / initial concentration) x 100 =


percent ionization = (0.000291 / 0.311)x 100 = 0.0936% = 0.094%

8 0

3 years ago