A neutron is in the nucleus. The isotope symbol consists of the mass number and atomic number. <span>The mass number is the number of neutrons and protons. </span>
<span>Therefore adding neutrons affects the mass number. This means the symbol is affected.</span>
Answer is: 4.0 mol of lithium nitride would be produced.
Balanced chemical reaction: 6Li + N₂ → 2Li₃N.
n(Li) = 12 mol; amount of substance.
From chemical reaction: n(Li) : n(Li₃N) = 6 : 2 (3 : 1).
n(Li₃N) = n(Li) ÷ 3.
n(Li₃N) = 12 mol ÷ 3.
n(Li₃N) = 4 mol; amount of lithium nitride.
Galvanizing protects from rust in a number of ways: It forms a barrier that prevents corrosive substances from reaching the underlying steel or iron. The zinc serves as a sacrificial anode so that even if the coating is scratched, the exposed steel will still be protected by the remaining zinc.
Answer:
CaCl₂
Step-by-step explanation:
The <em>empirical formula</em> is the simplest whole-number ratio of atoms in a compound.
The ratio of atoms is the same as the ratio of moles.
So, our job is to calculate the molar ratio of Ca to Cl.
Data:
Mass of Ca = 3.611 g
Mass of Cl = 6.389 g
Calculations
Step 1. <em>Calculate the moles of each element
</em>
Moles of Ca = 3.611 g Ca × (1 mol Ca/(40.08 g Ca)= 0.090 10 mol Ca
Moles of Cl = 6.389 g Cl
Step 2. <em>Calculate the molar ratio of the elements
</em>
Divide each number by the smallest number of moles
Ca:Cl = 0.090 10:0.1802 = 1:2.000
Step 3. Round the molar ratios to the nearest integer
Ca:Cl = 1:2.000 ≈ 1:2
Step 4: <em>Write the empirical formula
</em>
EF = CaCl₂
Answer:
All of the above processes have a ΔS < 0.
Explanation:
ΔS represents change in entropy of a system. Entropy refers to the degree of disorderliness of a system.
The question requests us to identify the process that has a negative change of entropy.
carbon dioxide(g) → carbon dioxide(s)
There is a change in state from gas to solid. Solid particles are more ordered than gas particles so this is a negative change in entropy.
water freezes
There is a change in state from liquid to solid. Solid particles are more ordered than liquid particles so this is a negative change in entropy.
propanol (g, at 555 K) → propanol (g, at 400 K)
Temperature is directly proportional to entropy, this means higher temperature leads t higher entropy.
This reaction highlights a drop in temperature which means a negative change in entropy.
methyl alcohol condenses
Condensation is the change in state from gas to liquid. Liquid particles are more ordered than gas particles so this is a negative change in entropy.
