a) To find the mass after t years:we will use this formula:
A = Ao / 2^n when A =the amount remaining
and Ao = the initial amount
and n = t / t(1/2)
by substitution:
∴ A = 200 mg/ 2^(t/30y)b) Mass after 90 y :by using the previous formula and substitute t by 90 y
A = 200mg/ 2^(90y/30y)
∴ A = 25 mgC) Time for 1 mg remaining:when A= Ao/ 2^(t/t(1/2)
so, by substitution:
1 mg = 200 mg / 2^(t/30y)
∴2^(t/30y) = 200 mg by solving for t
∴ t = 229 y
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3.74×
3.74 × molecules of propane were in the erlenmeyer flask.
number of moles of propane can be calculated as moles of propane.
mass of propane = 0.274 g
molar mass of propane = 44.1
So this gives us the value of 6.21×
moles of propane
No one mole of propane As a 6.0-2 × 
so, 6.21 × × 6. 022 × 10^23
= 3.74 ×
Therefore, molecules of propane were in the erlenmeyer flask is found to be 3.74 ×
<h3>What is erlenmeyer flask?</h3>
- A laboratory flask with a flat bottom, a conical body, and a cylindrical neck is known as an Erlenmeyer flask, sometimes known as a conical flask or a titration flask.
- It bears the name Emil Erlenmeyer after the German chemist.
<h3>What purpose does an Erlenmeyer flask serve?</h3>
- Liquids are contained in Erlenmeyer flasks, which are also used for mixing, heating, chilling, incubating, filtering, storing, and other liquid-handling procedures.
- For titrations and boiling liquids, their sloped sides and small necks make it possible to whirl the contents without worrying about spills.
To learn more about calculating total molecules visit:
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Answer:
114 kPa
Explanation:
Using Gay-Lussac's law you get the equation 
and converting celcius you get the final equation of 
. After dividing 85.5 by 27+273(300) you get 0.285 and then you multiply 0.285 by 127+273 (400). You finally get 114 kPa
The correct option is: CH4 + O2 → CO2 + H2O.
In writing chemical equations, the reactants are usually written to the left of the equation of the reaction while the products are written to the right of the reaction. An arrow pointing in the right direction shows the direction of the reaction. In the question given above, methane and oxygen are the reactants while carbon dioxide and water are the products. The options that states the chemical reaction correctly is option 1.
