Explanation:
Lead can cause effects on the blood, as well as the nervous, immune, renal and cardiovascular systems. ... Exposure to high amounts of lead can cause gastrointestinal symptoms, severely damage the brain and kidneys, and may cause reproductive effects. Large doses of some lead compounds have caused cancer in lab animals.
<u>Lithium Iodide</u><u>:</u>
~formed by the reaction of hydroxide with hydroiodic acid
Hope this helped you, have a good day bro cya)
<u>Given information:</u>
Concentration of HCl = 0.035 M
<u>To determine:</u>
pH of the solution
<u>Explanation:</u>
Hydrochloric acid, HCl is a strong acid. It will completely dissociate to give H+ and Cl- ions
HCl → H+ + Cl-
Hence the concentration of H+ = Cl- = 0.035M
Now, pH measures the strength of H+ ions in a given solution. It is expressed as:
pH = -log[H+]
pH (HCl) = -log(0.035) = 1.46
Ans: pH of 0.035M HCl is 1.46
A is obviously out because it leads to a volume of 125.0 milliliters of the new solution and gives you a lower concentration than you were aiming for.
D is out because you are adding 75 milliliters of the stock solution, so your concentration would be too high. You only need 25.0 milometers of stock solution per 100 milliliters of the new solution.
C is also out because it leads to 50.0 milliliters stock solution per 100 milliliters of the new solution and hence the wrong concentration.
B is by default the correct answer. It also details the correct technique. First you add the stock solution (This you know from your calculations to be 25 milliliters.) then you add the water up to the volume you needed. (Because the calculations only tell you the total volume of water not what you need to add) You also add the water last so you can rinse the neck of the flask to make sure you also get all the stock solution residue into the stock solution.
I would add the final step of stirring, but B is the only answer that can be correct.
Answer:
464.1 J absorbed.
Explanation:
Given data:
Specific heat of zinc = 0.39 J/g°C
Mass of zinc = 34 g
Temperature changes = 22°C to 57°C
Energy absorbed or released = ?
Solution:
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = 57°C - 22°C
ΔT = 35°C
Q = m.c. ΔT
Q = 34 g. 0.39 J/g°C. 35°C
Q = 464.1 J
