One mole of anything, including atoms, is
6.022
×
10
23
(Avogadro's number) of them. Usually you will have a given mass of an element. There are two basic steps to get from the given mass to the number of atoms. They are:
Mass
→
Moles
and
Moles
→
Atoms
Answer:
The combustion of 59.7 grams of methane releases 3320.81 kilojoules of energy
Explanation:
Given;
CH₄ + 2O₂ → CO₂ + 2H₂O, ΔH = -890 kJ/mol
From the combustion reaction above, it can be observed that;
1 mole of methane (CH₄) released 890 kilojoules of energy.
Now, we convert 59.7 grams of methane to moles
CH₄ = 12 + (1x4) = 16 g/mol
59.7 g of CH₄ 
1 mole of methane (CH₄) released 890 kilojoules of energy
3.73125 moles of methane (CH₄) will release ?
= 3.73125 moles x -890 kJ/mol
= -3320.81 kJ
Therefore, the combustion of 59.7 grams of methane releases 3320.81 kilojoules of energy
A single fixed pulley is used to lift load by changing the direction of the lifting force. Even though a single fixed pulley has no mechanical gain in that, the effort applied is greater than the load, it is preferred in use since you do not have to pull or push the pulley up and down.
Answer:
The answer to your question is: 6.55 x 10 ²³ atoms of Br
Explanation:
CH2Br2 = 37.9 g
MW CH2Br2 = (12 x 1) + (2 x 1) + (80 x 2) = 174 g
174 g of CH2Br2 ------------------ 160 g of Br2
37.9 g of CH2Br2 --------------- x
x = 37.9 x 160/174 = 34.85 g of Br
1 mol of Br ----------------- 160 g Br2
x ---------------- 174 g Be2
x = 174 x 1 /160 = 1.088 mol of Br2
1 mol of Br ----------------- 6.023 x 10 ²³ atoms
1.088 mol of Br ------------- x
x = 1.088 x 6.023 x 10 ²³ / 1 = 6.55 x 10 ²³ atoms
Answer: A. an electron
<u>Beta particles are electrons or positrons (electrons with positive electric charge or antielectrons).</u> Beta decay is a type of radioactive decay in which a beta ray is emitted from an atomic nucleus.
<u>Beta decay occurs when, in an unstable nucleus with too many protons or too many neutrons, one of the protons or neutrons transforms into the other.</u> In beta minus decay, a neutron is broken down into a proton, an electron, and an antineutrino (the neutrino antiparticle, meaning it has an opposite charge to the neutrino). In beta decay plus, a prototype breaks down into a neutron, a positron and a neutrino.
