Answer:
The forensic laboratory system in the United States consists of private and public labs. One well-known public lab is the FBI (the Federal Bureau of Investigation) Public labs are mostly run by police officers and state employees, while private labs are organized as a fee-for-service and they are small with a few large and medium=sized operations.
Explanation:
Idk and it's not even 100 points but I hope this helps.
Chemical. burning is a chemical change
Answer:
(4) CuO + H₂ → Cu + H₂O.
Explanation:
<em>(1) Cu + 2AgNO₃ → Cu(NO₃)₂ + 2Ag.</em>
It is considered as a single replacement reaction that Cu replaces Ag in its salt AgNO₃.
<em>(2) 2Cu + O ₂ → 2CuO.</em>
It is a combustion reaction that Cu reacts with oxygen results CuO.
<em>(3) CuCO₃ → CuO + CO₂.</em>
It is a decomposition reaction that CuCO₃ is decomposed to CuO and CO₂.
<em>(4) CuO + H₂ → Cu + H₂O.</em>
It is considered as a synthesis reaction that two reactants CuO and hydrogen are reacted to produce Cu and H₂O.
<em>So, the right choice is: (4) CuO + H₂ → Cu + H₂O.</em>
<em></em>
Answer:
Mass of hydrogen produced =2.28 g
Explanation:
Given data:
Mass of tin = 67.3 g
Mass of hydrogen produced = ?
Solution:
Chemical equation:
Sn + 2H₂O → SnO₂+ 2H₂
Number of moles of Sn:
Number of moles = mass/ molar mass
Number of moles = 67.3 g/ 118.71 g/mol
Number of moles = 0.57 mol
Now we will compare the moles of tin with hydrogen from balance chemical equation.
Sn : H₂
1 : 2
0.57 : 2×0.57 = 1.14
Mass of hydrogen:
Mass = number of moles ×molar mass
Mass = 1.14 mol × 2 g/mol
Mass = 2.28 g
