Answer is (b)
2,3,1 is the stoichiometry
The values in front of the elements are the stoichiometric values
(Since Al2Br6 has no value in front, it's considered 1)
Answer:

Explanation:
1. Convert decagrams to grams

2. Convert grams to decigrams
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Answer:
Option (A) the solid X is ground to a fine powder.
Explanation:
X(s) + 2B(aq) → X+(aq) + B2(g)
In the reaction above, the rate of the reaction will be highest, when X being a solid is ground to fine powder.
Grounding X to fine powder simply means increasing the surface area of X.
An increase in surface area of reactants will definitely increase the rate of reaction because the particles of the solid will collide with the right orientation and hence speed up the reaction rate.
Protons are Positively charged
Electrons are Negatively charged
Electrons are attracted to Protons
C) Electron
Hope this Helps!!!