If you start with 40.0 grams of the element at noon, 10.0 grams
radioactive element will be left at 2 p.m. The correct answer between
all the choices given is the second choice or letter B. I am hoping that this
answer has satisfied your query and it will be able to help you in your
endeavor, and if you would like, feel free to ask another question.
The pH of the solution is 1.38.
Mass of HCl = 614 mg = 0.614 g
Moles of HCl = 0.614g / 36.5 gmol⁻¹
Concentration of HCl :
Concentration= moles/volume of solution in liters
On adding 0.01682 moles to 400 mL of water that 0.4 L of water.
[HCl]=0.01682 mol/0.4 L= 0.04205 M
HCl (s) + H₂O (l) → H₃O⁺ (aq) +Cl⁻
1 mole of HCl gives 1 mole of hydronium ion and 1 mole of chloride ions in an aqueous solution.
Then 0.04205 mol/L of HCl will give:
1x0.04205 M= 0.04205 mol/L of hydronium ions.
[H₃O⁺]= 0.04205 M
pH= -log[H₃O⁺]
pH= -log[0.04205 M]
= 1.38
The pH of the solution is 1.38.
The complete question is- A chemist dissolves 614. mg of pure hydrochloric acid in enough water to make up 400 mL of solution. Calculate the pH of the solution. Round your answer to 3 significant decimal places. X 5 ?
Learn more about pH of the solution here-
brainly.com/question/11300720
#SPJ4
The answer would be modeling, because craving is when you take a block of something and slice it t make something,and casting is when you put layers over layers to form a something. so the answer will be modeling.