Answer: The concentration of unknown sample is 1.8 mg/ml
Explanation:
According to the dilution law,
where,
= concentration of stock solution = ?
= volume of stock solution = 0.25 ml
= concentration of diluted solution = 0.45 mg/ml
= volume of diluted solution = (0.25+0.75) ml = 1.00 ml
Putting in the values we get:
Therefore, concentration of unknown sample is 1.8 mg/ml
Answer:
Check the answers in the explanation
Explanation:
The following are the answers
(1) if the solution is colourless : The answer is B Cr207
(2) If the solution gives no apparent reaction with dilute hydrochloric acid, : The answer is A CO3
(3) if No odour can be detected when a sample of the solution is added drop by drop to a warm solution of sodium hydroxide : The answer is C NH4
(4) If No precipitate is formed when a dilute solution of H2SO4 is added to a sample of the solution : The answer is D ba
Answer:
3 moles H₂
Explanation:
The reaction equation Zn + 2HCl => ZnCl₂ + H₂ shows a 1:1 mole ratio between Zn and molecular hydrogen (H₁). Therefore, the moles of Zn consumed in the reaction is then equal to the moles of H₂ produced. In this case using 3 moles Zn => 3 moles H₂ will be produced.