To balance any redox equation, first divide the reaction into two half reactions, and balance the atom whose oxidation number is changing:
<span>NO2 --> NH3 </span>
<span>H2 --> H2O </span>
<span>Next, balance oxygens by adding H2O where needed, and then balance hydrogen by adding H+: </span>
<span>NO2 --> NH3 + 2 H2O </span>
<span>H2O + H2 --> H2O </span>
<span>7 H+ + NO2 --> NH3 + 2 H2O </span>
<span>H2O + H2 --> H2O + 2 H+ </span>
<span>Next, balance charges by adding electrons (e-): </span>
<span>7 H+ + NO2 + 7 e- --> NH3 + 2 H2O </span>
<span>H2O + H2 --> H2O + 2 H+ + 2 e- </span>
<span>Now, multiply one or both equations by small numbers to make the number of electrons the same in the two half reactions. In this case, multiply the top equation by 2 and the bottom one by 7 to give you 14 electrons in each half reaction: </span>
<span>14 H+ + 2 NO2 + 14 e- --> 2 NH3 + 4 H2O </span>
<span>7 H2O + 7 H2 --> 7 H2O + 14 H+ + 14 e- </span>
<span>Finally, add the two half reactions and simplify by cancelling anything that is on both sides. This will give you the final balanced reaction: </span>
<span>2 NO2 + 7 H2 --> 2 NH3 + 4 H2O </span>
<span>So, the answer to the original question is (A) 7
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Answer:
it can cause irritation in eyes throat and lungs and u can become lightheaded, or possibly fall in a coma
Answer : The final temperature of the mixture is 
Explanation :
In this problem we assumed that heat given by the hot body is equal to the heat taken by the cold body.
And as we know that,
Mass = Density × Volume
Thus, the formula becomes,
where,
= 
= specific heat of water = same
= 
= mass of water = same
= 
= density of water = 1.0 g/mL
= volume of water at 
= 
= volume of water at 
= 
= final temperature of mixture = ?
= initial temperature of water =
= initial temperature of water =
Now put all the given values in the above formula, we get:
Therefore, the final temperature of the mixture is
