<span>Percentage
by mass is the amount in mass of a component in a mixture per 100 unit of mass of the
total mixture. Percentage by mass is the same as %w/w. We can determine this by dividing the mass of the solute with the total mass of the mixture. However, from the problem statement, we are given the volume of the water so there is a need to convert this value to mass by using the density of water. We calculate as follows:
Mass of solution = 100 mL (0.99993 g/mL) water + 25 g EtOH
Mass of solution = 124.993 g solution
%w/w = 25 g / 124.993 g x100
%w/w = 20% of EtOH</span>
Answer:
B,C,D
Explanation:
The yield of CCl4 depends on the amount of CH4 in a 1:1 ratio. The amount of Cl2 is twice that of CH4 hence some must be left over. To ensure that all the Cl2 is used up, more CH4 must added to the system.
Answer:
Explanation:I would need more info to understand this question but explaining molecules is pretty easy tho
The problem talks about two questions and these are:
1. Metals are very good conductors of electricity and heat. Directing heat is easier. So let Marie heat the beads and also have heat another substance, for instance, water. If the beads heat quicker, then they are metals. Another test to conduct is called flame test. This test should give you a colored flame (blue/white for lead) the metal is lead if the reaction is: 2PbO+C ==> 2Pb +CO2
2. The beads are possibly to be lead since Ferrous(lead) oxide + carbon = carbon dioxide + lead