The 2 types of mechanical weathering are .....
1) * Temperature Change
-Temperature change makes rocks contract and expand
-Also one of the important cause of mechanical weathering.
2) * Abrasion
-Abrasion is a process in which an external force
Example: water movement or gravity which causes rock materials grind (reduce <<< synonyms) which can break apart the outer layers of affected rocks.*PLEASE GIVE THIS A THANKS :) :D xD AND ALSO THE BRAINIST ANSWER PREETTY PLEASEEEEEEEE, DON'T YOU EVER FEEL LIKE YOUR GOOOOING TO GIVE ME THE BRAINIEST ANSWER/CROWN??? xD
<span>It is a physical change. I goes from white, to yellow, back to white.</span>
Answer:
7. A) I, II
; 8. D) 2.34e9 kJ
Step-by-step explanation:
7. Combustion of ethanol
I. The negative sign for ΔH shows that the reaction is exothermic.
II. The enthalpy change would be different if gaseous water were produced.
That's because it takes energy to convert liquid water to gaseous water, and this energy is included in the value of ΔH.
III. The reaction is a redox reaction, because
- Oxygen is reacting with a compound
- The oxidation number of C increases
- The oxidation number of O decreases.
IV. The products of the reaction occupy a smaller volume than the reactants, because 3 mol of gaseous reactant are forming 2 mol of gaseous product.
Therefore, only I and II are correct.
7. Hindenburg
Data:
V = 2.00 × 10⁸ L
p = 1.00 atm
T = 25.1 °C
ΔH = -286 kJ·mol⁻¹
Calculations:
(a) Convert temperature to kelvins
T = (25.1 + 273.15) K = 298.25 K
(b) Moles of hydrogen
Use the <em>Ideal Gas Law</em>:
pV = nRT
n = (pV)/(RT)
n = (1.00 × 2.00 × 10⁸)/(0.082 06 × 298.25) = 8.172 × 10⁶ mol
(c) Heat evolved
q = nΔH = 8.172 × 10⁶ × (-286) = -2.34 × 10⁹ kJ
The hydrogen in the Hindenburg released 2.34e9 kJ
.
The answer would be using proportions 151/x=166/0.532, then you solve for x. The answer would be <span>0.483927711, but then you have to round it and get approximately 0.484 L. Hope this helps! Happy Studying!</span>
Answer:
<h2>0.52 moles </h2>
Explanation:
To find the number of moles in a substance given it's number of entities we use the formula

where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have

We have the final answer as
<h3>0.52 moles</h3>
Hope this helps you