Answer:
C. 30.0 g NaOH and add water until the final solution has a volume of 3.00 L.
Explanation:
Molarity of a substance , is the number of moles present in a liter of solution .
M = n / V
M = molarity
V = volume of solution in liter ,
n = moles of solute ,
from the question ,
M = 0.250M
V = 3.00 L
M = n / V
n = M * v
n = 0.250M * 3.00 L = 0.75 mol
Moles is denoted by given mass divided by the molecular mass ,
Hence ,
n = w / m
n = moles ,
w = given mass ,
m = molecular mass .
From the question ,
n = 0.75 mol NaOH
m = molecular mass of NaOH = 40 g/mol
n = w / m
w = n * m
w = 0.75 mol * 40 g/mol = 30.0 g
Hence , by using 30.0 g of NaOH and dissolving it to make up the volume to 3 L , a solution of 0.250 M can be prepared .
Answer:
Explanation:
Any substance that contains only one kind of an atom is known as an element. Because atoms cannot be created or destroyed in a chemical reaction, elements such as phosphorus (P4) or sulfur (S8) cannot be broken down into simpler substances by these reactions.
Example: Water decomposes into a mixture of hydrogen and oxygen when an electric current is passed through the liquid. Hydrogen and oxygen, on the other hand, cannot be decomposed into simpler substances. They are therefore the elementary, or simplest, chemical substances - elements.
Each element is represented by a unique symbol. The notation for each element can be found on the periodic table of elements.
The elements can be divided into three categories that have characteristic properties: metals, nonmetals, and semimetals. Most elements are metals, which are found on the left and toward the bottom of the periodic table. A handful of nonmetals are clustered in the upper right corner of the periodic table. The semimetals can be found along the dividing line between the metals and the nonmetals.
I believe that the answer to the question provided above is that molecules in solid are compact and are connected. It requires huge energy to move it, thus requires high temperature.
Hope my answer would be a great help for you. If you have more questions feel free to ask here at Brainly.
In order to answer this question we might first want to think about what is electromagnetic radiation. In essence it’s light, just some of the wavelengths are too long or too short for us to see.
We can think about it as two oscillating sinusoidal (goes up and down) waves, one is electric, the other is magnetic.
Because we’re dealing in waves, that means we can calculate their frequency, wavelength, amplitude (brightness) and period.
To calculate it we can use E=hc/lambda
Where E = jewels of energy
h = Planck’s constant
c = speed of light
Lambda = wavelength
It doesn’t really matter for this question what those things mean, just note that it takes more energy to have a shorter wavelength, or less energy to have a longer wavelength.
So now we can answer the question. Light of a longer wavelength has less energy than that of a shorter wavelength. So, when long wavelengths are absorbed by matter (atoms) they will give those atoms less energy. So, either it will pass through the object entirely or it will make the atoms vibrate a little bit more than they already are and we call that thermal energy, or heat.
If high energy wavelengths are passing through matter then they will be giving those atoms a lot of energy, sometimes even ionizing the atoms.
Which, if you’re a living thing can be very bad for your cells.
I hope that helps.
