A chemical equation does not give information about the following:
- It usually does not give the "state of the substances". There are three states: Solid(s), liquid(q) and gas(vap).
- The chemical equation does not show whether it is complete or incomplete.
- The "speed of the reaction" is not mentioned.
- The "concentration of the substance" whether it is diluted or concentrated is not mentioned.
- The "rate of the reaction", temperature, catalyst, pressure etc is not mentioned. These can be mentioned "above or below the arrow".
<h2>It can happen when liquids are cold or when they are warm. ... It turns out that all liquids can evaporate at room temperature and normal air pressure. Evaporation happens when atoms or molecules escape from the liquid and turn into a vapor. Not all of the molecules in a liquid have the same energy.</h2>
Which statement describes how the binary ionic compound KBr is named? The metal is named first, and the name is unchanged. Which of these is a property of a substance that is composed of atoms that are held together by ionic bonds?
Answer: In simplest case mass of reactants is same as mass of products.
Without thinking this question deeper, mass of ZnCl2 would be 49, but..
Explanation: Reaction should be Zn + 2 HCl ⇒ ZnCl2 + H2
Amount of zinc is 5 g / 65,38 g/mol = 0,076476 mol and amount
of Hydrogen Chloride is 50 g / 36.458 g/mol = 1,371 mol.
Althought HCl is needed 0.152 moles, zinc is an limiting reactant.
So it is possible to produce only 0.076476 mol Hydrogen and its mass
is 0.154 g. Mass of ZnCl2 would be 0.076476 mol · (65.38 + 2·35.45) =
10.42 g
