Answer:
e. 18
Explanation:
A neutral P atom has an atomic number of 15, which means there are 15 protons in the atom. In order to be neutral, the P atom must also have 15 electrons.
The P³⁻ anion has 3 electrons more than the neutral P atom since it has a charge of -3.
Thus, the total number of electrons are 15 + 3 = 18 electrons.
Answer:
Number of moles of methane form = 2.3 mol
Explanation:
Given data:
Number of moles of Hydrogen = 4.6 mol
Number of moles of methane form = ?
Solution:
Chemical equation:
C + 2H₂ → CH₄
Now we will compare the moles of methane with hydrogen from balance chemical equation.
H₂ : CH₄
2 : 1
4.6 : 1/2×4.6 = 2.3 mol
Form 3.6 moles of hydrogen 2.3 moles of methane can be formed.
Answer:

Explanation:
The pressure, the volume and the temperature of an ideal gas are related to each other by the equation of state:

where
p is the pressure of the gas
V is the volume of the gas
n is the number of moles
R is the gas constant
T is the absolute temperature
For the gas in this problem:
n = 2.00 mol is the number of moles
V = 17.4 L is the gas volume
p = 3.00 atm is the gas pressure
is the absolute temperature
Solving for R, we find the gas constant:

Answer:
2.41x10²¹ atoms
Explanation:
mass of nickel that are present in the coin can be determined Using ( 25% nickel) with j mass of coin= 0.942g )
mass of nickel = (0.942g) × (25/100)
= 0.2355g of Nickel
We need to convert this " gram" into " moles"
Mole= mass/ molar mass
Molar mass= 58.69 g/mol
0.2355 g) / (58.69 g/mol)
= 0.004 mol
We need to convert the moles to
number of atoms.
Avogadro's number= 6.023x10²³ atoms/mol
(0.004 × 6.023x10²³ atoms/mol)
=2.41x10²¹ atoms