If you start with 40.0 grams of the element at noon, 10.0 grams
radioactive element will be left at 2 p.m. The correct answer between
all the choices given is the second choice or letter B. I am hoping that this
answer has satisfied your query and it will be able to help you in your
endeavor, and if you would like, feel free to ask another question.
Answer:
Equal volumes of SO2(g) and O2(g) at STP contain the same number of molecules
Explanation:
According to Avogadro Law,
Equal volume of all the gases at same temperature and pressure have equal number of molecules.
This law state that volume and number of moles of gas have direct relation.
When the amount of gas increases its volume will increase and when the amount of gas decreases its volume will decrease.
Mathematical relation:
V ∝ n
V/n = K
K is proportionality constant.
When number of moles change from n₁ to n₂ and volume from V₁ to V₂
expression will be,
V₁/n₁ = K , V₂/n₂ = K
V₁/n₁ = V₂/n₂
Answer:
0.9975 cup
Step-by-step explanation:
"Unrefined dark crystalline sugar" is what non-chemists call "brown sugar."
200.0 g brown sugar = 1 cup
199.5 g brown sugar = 199.5× 1/200
.0
199.5 g brown sugar = 0.9975 cup
A standard measuring cup is not capable of this precision and, furthermore, the mass of brown sugar you can get into a cup depends on how tightly you pack it.
Your Mole Day cake will be fine if you use 1 cup of brown sugar as usual.
Physical change - No change of matter in this phase
chemical change - All types of phase change occur here
I have not read the article, and so I don't know in what context this is referring to. But I do know that <span>Infra-sound is made up of a really low frequency sound, beyond the range of hearing by humans. </span>Helpful? :)
