Answer: 12 atoms
Explanation: the equation has 6H2 i.e
6*2 = 12
Rdaioactive decay results in the formation of a different element. Plutonium decays by emitting alpha emission to form uranium. Thermal energy is emitted as the alpha particles are absorbed and the kinetic energy is converted to heat. The amount of energy is computed by the formula;
E = mc²
E = 0.000046 × (3 ×10^8)
Energy = 4.14 ×10^13 Joules
Question:
Zinc metal is added to hydrochloric acid to generate hydrogen gas and is collected over a liquid whose vapor pressure is the same as pure water at 20.0 degrees C (18 torr). The volume of the mixture is 1.7 L and its total pressure is 0.987 atm. Determine the number of moles of hydrogen gas present in the sample.
A. 0.272 mol
B. 0.04 mol
C. 0.997 mol
D. 0.139 mol
E. 0.0681 mol
Answer:
The correct option is;
E. 0.0681 mol
Explanation:
The equation for the reaction is
Zn + HCl = H₂ + ZnCl₂
Vapor pressure of the liquid = 18 torr = 2399.803 Pa
Total pressure of gas mixture H₂ + liquid vapor = 0.987 atm
= 100007.775 Pa
Therefore, by Avogadro's law, pressure of the hydrogen gas is given by the following equation
Pressure of H₂ = 100007.775 Pa - 2399.803 Pa = 97607.972 Pa
Volume of H₂ = 1.7 L = 0.0017 m³
Temperature = 20 °C = 293.15 K
Therefore,

Therefore, the number of moles of hydrogen gas present in the sample is n ≈ 0.0681 moles.
Answer:
.14L or 140mL
Explanation:
This is a classic plug-n-chug problem. Your textbook probably goes over this formula as
. M stands for molarity of the given substance, and V stands for the volume that the substance occupies.
Simply plug in the values that you're given, like so:


After completing the algebra portion and solving for the unknown, you will be left with x = .14L, which is the volume required to neutralize 30mL of 7M NaOH.
Answer:
0.5 mol
Explanation:
Given data:
Number of atoms of He = 3.01 ×10²³
Number of moles = ?
Solution:
Avogadro number:
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.02 × 10²³ is called Avogadro number.
1 mole = 6.02 × 10²³ atoms
3.01 ×10²³ atoms × 1 mol / 6.02 × 10²³ atoms
0.5 mol