All categories

3 years ago

What are the similarities between molecules and elements

1 answer:

7 0

A molecule is formed when two or more atoms join together chemically. A compound is a molecule that contains at least two different elements. All compounds are molecules but not all molecules are compounds.

Molecular hydrogen (H2), molecular oxygen (O2) and molecular nitrogen (N2) are not compounds because each is composed of a single element. Water (H2O), carbon dioxide (CO2) and methane (CH4) are compounds because each is made from more than one element. The smallest bit of each of these substances would be referred to as a molecule. For example, a single molecule of molecular hydrogen is made from two atoms of hydrogen while a single molecule of water is made from two atoms of hydrogen and one atom of oxygen.

You might be interested in

What is the frequency of radiation whose wavelength is 2.25 X 10^-5cm?

Semenov [28]

Answer:

1.25 x 10^15Hz

Explanation:

c = frequency x wavelength

c is the speed of light, which is equal to 3.00 x 10^8 m / s

frequency = c /wavelength

= (3.00 x 10^8m /s) / (2.40 x 10^-5 cm x 1 m /100cm)

= (3.00 x 10^8 m/s) / 2.40 x 10^-7m

= 1.25 x 10^15/s 1 / s = 1Hz

So, the Frequency = 1.25 x 10^15Hz

I hope this helped :)

3 0

3 years ago

Calculate the percent ionization of propionic acid (C2H5COOH) in solutions of each of the following concentrations (Ka is given

tekilochka [14]

Answer:

a) = 0.704%

b) = 1.30%

c) = 2.60%

Explanation:

Given that:

$K_a$ = $1.34*10^{-5$

For Part A; where Concentration of A = 0.270 M

Percentage Ionization(∝) $\alpha = \sqrt{\frac{K_a}{C} }$

$\alpha = \sqrt{\frac{1.34*10^{-5}}{0.270} }$

$\alpha = \sqrt{4.9629*10^{-5}}$

$\alpha = 7.044*10^{-3$

percentage% (∝) = $7.044*10^{-3}*100$

= 0.704%

For Part B; where Concentration of B = $7.84*10^{-2$ M

$\alpha = \sqrt{\frac{1.34*10^{-5}}{7.84*10^{-2}} }$

$\alpha = \sqrt{1.709*10^{-4} }$

$\alpha = 0.0130\\$

percentage% (∝) = 0.0130 × 100%

= 1.30%

For Part C; where Concentration of C= $1.92*10^{-2} M$

$\alpha = \sqrt{\frac{1.34*10^{-5}}{1.97*10^{-2}} }$

$\alpha = \sqrt{6.802*10^{-4}}$

$\alpha =0.02608$

percentage% (∝) = 0.02608 × 100%

= 2.60%

7 0

3 years ago

If a 0.10 M solution of a colored substance has a maximum absorbance at 500 nm and an absorbance of 0.26 M at this wavelength, w

Mashcka [7]

Absorbance is related to the concentration of a substance using the Beer-Lambert's Law. According to this law, absorbance is linearly related to concentration. However, this is only true up to a certain concentration depending on the substance. For this case, we assume that the said law is applicable.

A = kC
Using the first conditions, ewe solve for k.
0.26 = k (0.10)
k = 2.6

A = kC
A = 2.6 (0.20) = 0.52

Therefore, the absorbance at a concentration of 0.20 M and wavelength of 500nm is 0.52.

7 0

3 years ago

Can someone provide a answer with explanation for this question? Thanks!

zhuklara [117]

Answer:

Explanation:

4 0

1 year ago

What is the freezing point of an aqueous 1.58 molal nacl solution?

Alina [70]

<span>Tf is the freezing point of the solution(the solvent plus solute). T*f is the freezing point of the pure solvent(without solute) i is the van't Hoff factor.It is approximately the number of particles in solution that are made for each particle of the solute that is placed into solution.Therefore, for nonelectrolytes, i = 1. Kf is the freezing point depression constant.For water, Kf = 1.86 Degree C/m, or 1.86 Degree C.kg/mol. Tf is -1.58 Degree C</span>

4 0

3 years ago