Answer:
this is your answer
Explanation:
Silicon, like carbon, is relatively inactive at ordinary temperatures; but when heated it reacts vigorously with the halogens (fluorine, chlorine, bromine, and iodine) to form halides and with certain metals to form silicides.
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Answer : The initial temperature of system 2 is, 
Explanation :
In this problem we assumed that the total energy of the combined systems remains constant.
The mass remains same.
where,
= heat capacity of system 1 = 19.9 J/mole.K
= heat capacity of system 2 = 28.2 J/mole.K
= final temperature of system =
= initial temperature of system 1 =
= initial temperature of system 2 = ?
Now put all the given values in the above formula, we get
Therefore, the initial temperature of system 2 is, 
Answer: The reactivity of acetic acid with various chemicals (A)
Explanation: engenuity 2021
In the compound nh3, nitrogen has an oxidation number of 3+ and hydrogen has an oxidation number of -1
The molecule NH3 have a neutral charge so the number of oxidation number of it's component must be equal to zero. The molecule NH composed of 1 nitrogen and 3 hydrogens. If the nitrogen oxidation number is 3+, then hydrogen would be:
1* N + 3*H=0
1*+3 +3*H=0
3H= -3
H= -1