Answer: d
Explanation: I got it right
Answer:
24.9 L Ar
General Formulas and Concepts:
<u>Atomic Structure</u>
- Reading a Periodic Table
- Moles
- STP (Standard Conditions for Temperature and Pressure) = 22.4 L per mole at 1 atm, 273 K
<u>Aqueous Solutions</u>
<u>Stoichiometry</u>
- Using Dimensional Analysis
Explanation:
<u>Step 1: Define</u>
[Given] 40.0 g Ar
[Solve] L Ar
<u>Step 2: Identify Conversions</u>
[PT] Molar Mass of Ar - 39.95 g/mol
[STP] 22.4 L = 1 mol
<u>Step 3: Convert</u>
- [DA] Set up:

- [DA] Divide/Multiply [Cancel out units]:

<u>Step 4: Check</u>
<em>Follow sig fig rules and round. We are given 3 sig figs.</em>
24.9235 L Ar ≈ 24.9 L Ar
<u>Answer:</u> The chemical equation is 
<u>Explanation:</u>
There are 2 types of reactions that are classified based on enthalpy change:
- Endothermic reaction
- Exothermic reaction
Endothermic reactions: They are defined as the reactions where heat is absorbed by the reaction. The change in enthalpy of the reaction is always positive.
Exothermic reactions: They are defined as the reactions where heat is released by the reaction. The change in enthalpy of the reaction is always negative.
Given values:
Energy released for 1 mole of HCl reacted = -42.1 kCal
The chemical equation for the formation of ammonium chloride follows:

Answer:
A. Distance = 18 m
time = 2 hr
speed = 9 m/hr
Explanation:
Speed is the same thing as velocity.
Velocity = distance/time
18m/2hr = 9m/hr
For choice B, the numbers are right, but the units are mixed (minutes were changed to hours)