There are a total of four quantum numbers that govern the
electrons. These are the principal quantum number (n), the angular quantum
number (l), the magnetic quantum number (ml) and lastly the spin quantum number
(ms). Each electron has a unit set of the four quantum numbers.
Since the first 3 quantum numbers is already specified, so
the remaining to be filled is the ms quantum number which can only have values
of +1/2 and -1/2. So we have 2 electrons.
Answer:
<span>2 electrons</span>
The correct answer is A. A test tube of zinc oxide. Zinc oxide is a compound which is a pure substance composed of two or more elements. They can only be separated or broken down into its individual elements or smaller compounds by chemical means. Therefore, the answer is a test tube of zinc oxide.
<u>Given:</u><u> </u>
Mass of Nitrogen (N₂) gas = 75 grams
<u>Finding the number of moles of N₂:</u><u> </u>
We know that the molar mass of N₂ is 28 grams/mole
Number of moles = Given mass / Molar mass
Number of moles = 75 / 28
Number of moles = 2.68 moles
Hence, there are 2.68 moles in 75 grams of Nitrogen Gas
Answer:
0.0102 L or 10.2 mL
Explanation:
From the question given above, the following data were obtained:
Molarity = 0.250 M
Mole = 0.00255 mole
Volume =?
Molarity is simply defined as the mole of solute per unit litre of the solution. Mathematically, it is expressed as:
Molarity = mole / Volume
With the above formula, we can obtain the volume as follow:
Molarity = 0.250 M
Mole = 0.00255 mole
Volume =?
Molarity = mole / Volume
0.250 = 0.00255 / volume
Cross multiply
0.250 × volume = 0.00255
Divide both side by 0.250
Volume = 0.00255 / 0.250
Volume = 0.0102 L
Covert 0.0102 L to mL.
1 L = 1000 mL
Therefore,
0.0102 L = 0.0102 L × 1000 / 1 L
0.0102 L = 10.2 mL
Thus, the volume is 0.0102 L or 10.2 mL
