Answer:
D. A bar magnet with its south pole on the left.
Explanation:
Answer:
c) CH₃Cl
Explanation:
Due the relative abundance of chlorine and bromine. It is possible to determine which of the halogens is present in a mass spectrum of a organic compound:
The Cl-35, Cl-37 have a relative abundance of 75/25; Br-79 and Br-81 of 50/50.
For that reason, if a compound has a M/M+2 ratio of 75:25 you can be sure the compound has 1 Cl in its structure. Thus, the only possible structure is:
<h3>
c) CH₃Cl</h3>
Answer:
6.25 g
Explanation:
From the question given above, the following data were obtained:
Half-life (t½) = 68.8 years
Time (t) = 344 years
Original amount (N₀) = 200 g
Amount remaining (N) =?
Next, we shall determine the number of half-lives that has elapsed. This can be obtained as follow:
Half-life (t½) = 68.8 years
Time (t) = 344 years
Number of half-lives (n) =
n = t / t½
n = 344 / 68.8
n = 5
Thus, 5 half-lives has elapsed.
Finally, we shall determine the amount of the Uranium-232 that remains. This can be obtained as follow:
Original amount (N₀) = 200 g
Number of half-lives (n) = 5
Amount remaining (N) =?
N = 1/2ⁿ × N₀
N = 1/2⁵ × 200
N = 1/32 × 200
N = 200 / 32
N = 6.25 g
Thus, the amount of Uranium-232 that remains is 6.25 g
Answer: The final temperature of nickel and water is .
Explanation:
The given data is as follows.
Mass of water, m = 55.0 g,
Initial temp, ,
Final temp, = ?,
Specific heat of water = 4.184 ,
Now, we will calculate the heat energy as follows.
q =
=
Also,
mass of Ni, m = 15.0 g,
Initial temperature, ,
Final temperature, = ?
Specific heat of nickel = 0.444
Hence, we will calculate the heat energy as follows.
q =
=
Therefore, heat energy lost by the alloy is equal to the heat energy gained by the water.
= -()
=
Thus, we can conclude that the final temperature of nickel and water is .
Answer:
Forensic methods and techniques.
Explanation:
Forensic methods and techniques include preparing for the execution of the examination, the examination, the collection of objects and samples, the preparation of evidence for laboratory expert evaluation, the interpretation and reporting of evidence.
The purpose of these techniques is to gather evidence to establish the truth.
The main goals of forensics are the reconstruction of the crime, the identification of the suspects, the determination of the motive of the crime, the arrest of the suspect. Forensics research is based on biology, physics, and chemistry. Forensics is one of the most important categories of criminalistics today.