Answer:
0.0277 M.
Explanation:
The integral rate law of a first order reaction:
<em>Kt = ln ([A₀]/[A]),</em>
where, k is the rate constant of the reaction <em>(k = 3.36 × 10⁻⁵ s⁻¹)</em>,
t is the time of the reaction <em>(t = 235.0 min = 14100 s)</em>,
[A₀] is the initial concentration of cyclopropane <em>([A₀] = 0.0445 M)</em>
<em>∵ Kt = ln ([A₀]/[A]),</em>
∴ (3.36 × 10⁻⁵ s⁻¹)(14100 s) = ln (0.0445 M)/[A]
Taking the exponential of both sides:
1.6 = (0.0445 M)/[A]
<em>∴ [A] = (0.0445 M)/1.6 = 0.0277 M.</em>
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According to an article dated back in February 8, 1992 which is entitled, “Science: Stardust is made of diamonds” on a website called newscientist (https://www.newscientist.com/article/mg13318073-000-science-stardust-is-made-of-diamonds/), American astronomers believed that diamonds are made in supernova explosions. It was said that the diamonds were the foundation of uncommon combinations of isotopes found in some meteorites. Donald Clayton of Clemson University in South Carolina suggested that the weightiest isotopes were more common in meteorites for the reason that the rare gases shaped in the neutron-rich outcome of a supernova explosion. Clayton also said, “the observed mixture of isotopes could have been produced only during the collapse of a massive star to form a neutron star”. This happens in a Type II explosion, for example the Supernova 1987A in the Large Magellanic Cloud. And rare gases like xenon become stuck in both weighty and light isotopes after the ejected gas from such a supernova cools down enough to create dust. The existence of the diamonds with these unusual gases in meteorites infers an alike source. Some of the carbon in the supernova fragments produces ordinary graphite dust, whereas some produces diamond dust. Considerable amount of stardust may be made of diamonds, if Clayton was not mistaken.
I would think that b would be the right answer
Answer:- 
atoms.
Solution:- We have been given the grams of carbon tetrachloride and asked to calculate the number of atoms of chlorine. It is a three step conversion problem. In the first we convert the grams of carbon tetrachloride to moles of it. In second step we convert moles of carbon tetrachloride to moles of chlorine and in the third step we convert the moles of chlorine to atoms of chlorine.
For grams to mole conversion we need the molar mass of the compound. Molar mass of carbon tetrachloride is 153.82 grams per mol. If we look at the formula of carbon tetrachloride then four chlorine are present in it. It means 1 mol of carbon tetrachloride has four moles of chlorine. The calculations are as follows:
= atoms
So, there are atoms in 12.2 grams of 
.
Answer:
Oiling is done on a regular basis to sewing Machine because in the machine there are lots of machinery parts i.e. wheels and axels, etc. which are in continuous use and they possess so much frictional force between them that wear tear may be observed in those parts.
