Critical Thinking Questions
1. Why do you think forensic scientists are so careful that the tests they do are sensitive, reproducible, and specific? What might happen if they were less careful about this?
They have to be careful to ensure as much accuracy as possible.
2.Which type of evidence do you think is most useful in an investigation? Why?
Physical evidence would probably be most important because it is the best way to connect someone directly with that crime.
3.Why do you think that forensic scientists continue to look for class characteristics given their limitations?
Class characteristics are good in court because it provides details of different aspects of the crime.
<span>
As a liquid is heated, its vapor pressure increases until the vapor pressure
equals the pressure of the gas above it.
Bubbles of vaporized liquid (i.e., gas) form within the bulk liquid and
then rise to the surface where they burst and release the gas. (At
the boiling temperature the vapor inside a bubble has enough pressure to
keep the bubble from collapsing.)
In order to form vapor, the molecules of the liquid must overcome the forces
of attraction between them.<span>
The temperature of a boiling liquid remains constant, even when more heat
is add.</span></span>
Gypsum has the same hardness as a fingernail
<span>The correct answer is, Alkali Metals</span>
Molecular mass of C₂H₄ is,
M = 2×12 + 4×1 g/mol
M = 28 g/mol
Moles of C₂H₄ in 5.6 g of C₂H₄ :
n = 5.6/28 mol
n = 0.2 mol
Now, 1 mol of C₂H₄ contains 2 moles of carbon.
So, number of moles of carbon are :
n = 0.4 mol
We know, 1 mol of any atom contains 6.022 × 10²³ atoms.
So, number of carbon atoms are :
Hence, this is the required solution.
