In the process of photosynthesis, when a glucose molecule is formed, THE HEAT CONTENT OF THE REACTION INCREASES, THUS, THE VALUE OF Q IS POSITIVE.
There are two types of chemical reaction, these are exothermic and endothermic reaction. Exothermic reactions are those reactions that gives off heat when they are occurring while endothermic reactions are those reactions that absorb heat from their environment during the course of reaction. Photosynthesis is an endothermic reactions; it absorbs energy from the environment when it is occurring, thus, the heat content of the product is always more than that of the reactants. The heat content of compounds are represented by letter q. For photosynthesis, q is positive, because there is an increase in the heat content of the product [glucose] formed.
Answer:
2HBr + Pb(NO₃)₂ → PbBr₂ + 2HNO₃
Explanation:
Hydrobromic acid (HBr), reacts with lead (II) nitrate (Pb(NO₃)₂) producing Lead(II) bromide (PbBr₂) and nitric acid (HNO₃). The reaction is:
HBr + Pb(NO₃)₂ → PbBr₂ + HNO₃
This reaction is unbalanced. You can see in products 2 Bromides but in reactants just 1. And in reactants 2 NO₃ but as product just 1. Thus, you can balance the equation, thus:
<em>2HBr + Pb(NO₃)₂ → PbBr₂ + 2HNO₃</em>
And this equation is the answer of your question!
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Answer : The molar concentration of ethanol in the undiluted cognac is 8.44 M
Explanation :
Using neutralization law,

where,
= molar concentration of undiluted cognac = ?
= molar concentration of diluted cognac = 0.0844 M
= volume of undiluted cognac = 5.00 mL = 0.005 L
= volume of diluted cognac = 0.500 L
Now put all the given values in the above law, we get molar concentration of ethanol in the undiluted cognac.


Therefore, the molar concentration of ethanol in the undiluted cognac is 8.44 M