Explanation:
A chemical property is defined as the property that brings changes in chemical composition of a substance.
For example, flammability, combustion, reactivity, electronegativity etc are allchemical properties.
On the other hand, a property that does not bring any change in chemical composition of a substance is known as a physical property.
For example, shape, size, mass, density etc are all physical properties.
Thus, we can conclude that these may all be classified as chemical properties of a substance.
Explanation:
The weak intermolecular forces which can arise either between nucleus and electrons or between electron-electron are known as dispersion forces. These forces are also known as London dispersion forces and these are temporary in nature.
Therefore, more is the surface area occupied by the carbon chain more will be the dispersion forces present in it. Hence, less is the surface area occupied by a molecule less will be the dispersion forces present in it.
Hence, the given molecules are organized from largest to smallest dispersion forces as follows.
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Answer:
Explanation:
The given reaction equation is:
2A + 4B → C + 3D
We know the mass of compound A in the reaction above. We are to find the mass of compound D.
We simply work from the known mass to calculate the mass of the unkown compound D
Using the mole concept, we can find the unknown mass.
Procedures
- We first find the molar mass of the compound A from the atomic units of the constituent elements.
- We then use the molar mass of A to calculate its number of moles using the expression below:
Number of moles of A = 
- Using the known number of moles of A, we can work out the number of moles of D.
From the balanced equation of the reaction, it is shown that:
2 moles of compound A was used up to produced 3 moles of D
Then
x number of moles of A would give the number of moles of D
- Now that we know the number of moles of D, we can find its mass using the expression below:
Mass of D = number of moles of D x molar mass of D
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