Answer: D is right
Explanation: One mole contains 6.0225 ·10^23 molecules
Despite of the substance
The steps to be followed while cleaning volumetric glassware are:
1. Remnants from the previous measurements are wiped off with the help of paper towel.
2. The glassware is then soaked overnight in warm soap solution.
3. Then before rinsing with tap water, the glassware are scrubbed with an appropriate brush.
4. After scrubbing, the glassware is rinsed thoroughly with tap water in order to make sure there are no traces of soap solution.
5. The glassware is then rinsed with de-ionized water and finally with the solution that would be used for the volumetric measurement.
Follow
these steps to solve the given equation:
Multiply
the two decimal figures together and find the sum of the exponents, that is,
(1.5
* 1.89) * 10 ^4+3
(2.835)
* 10^7
10^7
can also be written as e.70
'e'
stands for exponential.
Therefore,
we have 2. 835 e 7.0 = 2.8 e 7.0.
Based on the calculations above, the correct option is A.
The term formula units means molecules.
Then, what you are looking for is the mass in 4.59*10^24 molecules.
The procedure involves to convert the 4.59 * 10^24 molecules into moles and use the molar mass of the sodium chloride.
1) Number of moles = 4.59 * 10^24 molecules / (6.02 * 10^23 molecules/mol) = 7.62 mol
2) Molar mass of NaCl = 22.99 g/mol + 35.45 g/mol = 58.44 g/mol
3) mass of NaCl = molar mass * number of moles = 58.44 g/mol * 7.62 mol = 445.31 g of NaCl
Answer: 445.31 g of NaCl.
The empirical formula is N₂O₅.
The empirical formula is the <em>simplest whole-number ratio of atoms</em> in a compound.
The ratio of atoms is the same as the ratio of moles, so our job is to calculate the <em>molar ratio of N:O</em>.
I like to summarize the calculations in a table.
<u>Element</u> <u>Moles</u> <u>Ratio¹ </u> <u> ×2² </u> <u>Integers</u>³
N 1.85 1 2 2
O 4.63 2.503 5.005 5
¹To get the molar ratio, you divide each number of moles by the smallest number (1.85).
²Multiply these values by a number (2) that makes the numbers in the ratio close to integers.
³Round off the number in the ratio to integers (2 and 5).
The empirical formula is N₂O₅.
