Lets do process of elimination!
A. Breaking glass - That is a psychical change because if you break it, it is still glass. It didn't change to another substance.
B. Melting ice on a windshield - During the melting process, there is no chemical change, and therefore, no new substance is created.
C. Burning gasoline - When gas burns it usually combines with oxygen to give carbon dioxide, water etc. It is a chemical change.
D. Denting a bumper - The bumper is still a bumper, only thing is it has a dent in it. The properties did not change, meaning no chemical change.
Answer: 0.18 M
Explanation:
Initial molarity, M1 = 0.8 M
Initial olume, V1 = 225 ml
Final volume, V2 = 1000 ml
Final Molarity, M2 = M1V1/V2
= 0.8 x 225/1000
= 0.18 M
The kinetic molecular theory<span> of gases is stated in the following four </span>principles<span>: The space between gas </span>molecules<span> is much larger than the </span>molecules<span> themselves. Gas </span>molecules<span> are in constant random motion. The average </span>kinetic<span> energy is determined solely by the temperature.
I got this from my notes from my chemistry class last semester
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Answer:
B. Atoms in the original substances are arranged in a different way to make new substances.
Explanation:
The best statement that describes a change that occurs in a chemical reaction is that atoms in the original substances are arranged in a different way to make new substances.
- Chemical reactions obey the law of conservation of matter.
- The law postulates that "matter is neither created nor destroyed in a chemical reaction but they are simply rearranged".
- Therefore, atoms of compounds forms new bonds by rearranging to give a new product.
The relative molecular mass of the gas : 64 g/mol
<h3>Further explanation</h3>
Given
Helium rate = 4x an unknown gas
Required
The relative molecular mass of the gas
Solution
Graham's Law
r₁=4 x r₂
r₁ = Helium rate
r₂ = unknown gas rate
M₁= relative molecular mass of Helium = 4 g/mol
M₂ = relative molecular mass of the gas
Input the value :
