You want to divide by avagadros number (6.22 x 10^23). This will cancel the atoms unit and give moles, moles of Iridium. Now you want to calculate the atomic mass of Iridium which is in units of grams per mole. Multiply these two numbers and the moles will cancel giving you grams.
Setting up a dimension analysis type of thing helps tremendously. See what you have to cancel in order to get what you want. We canceled the atoms, then we canceled the moles, and then we got grams.
Answer:
A. 4.5 mol Mg(OH)₂
B. 6 mol NaOH
Explanation:
Let's consider the following balanced equation.
Mg(NO₃)₂ + 2 NaOH ⇒ Mg(OH)₂ + 2 NaNO₃
PART A
The molar ratio of NaOH to Mg(OH)₂ is 2:1. The moles of Mg(OH)₂ produced from 9 moles of NaOH are:
9 mol NaOH × 1 mol Mg(OH)₂/2 mol NaOH = 4.5 mol Mg(OH)₂
PART B
The molar ratio of NaOH to NaNO₃ is 2:2. The moles of NaOH needed to produce 6 moles of NaNO₃ are:
6 mol NaNO₃ × 2 mol NaOH/2 mol NaNO₃ = 6 mol NaOH
Explanation:
Energy makes molecules in the air move faster and expand, decreasing density. The opposite is true for cold air. Molecules are closer together, and absorb less energy.
Answer: D
Explanation:
A reducing agent is a species that reduces other compounds, and is thereby oxidized. The whole compound becomes the reducing agent. In other words, of a compound is oxidized, then they are the reducing agent. On the other hand, if the compound is reduced, it is an ozidizing agent.
Since we have established that a reducing agent is the compound being oxidized, we know that A is not our answer. An oxidized compound is losing electrons. Choice A states exactly this.
For B, this is true as we have established this already.
C is also correct. Since a reducing agent loses electrons, it becomes more positive. This makes the oxidation number increase.
D would be our correct answer. It is actually a good oxidizing agent is a metal in a high oxidation state, such as Mn⁷⁺.
Answer:
3.6667
Explanation:
<u>For helium gas:</u>
Using Boyle's law
Given ,
V₁ = 3.0 L
V₂ = 9.0 L
P₁ = 5.6 atm
P₂ = ?
Using above equation as:
<u>The pressure exerted by the helium gas in 9.0 L flask is 1.8667 atm</u>
<u>For Neon gas:</u>
Using Boyle's law
Given ,
V₁ = 4.5 L
V₂ = 9.0 L
P₁ = 3.6 atm
P₂ = ?
Using above equation as:
<u>The pressure exerted by the neon gas in 9.0 L flask is 1.8 atm</u>
<u>Thus total pressure = 1.8667 + 1.8 atm = 3.6667 atm.</u>