Answer:
After 18 hours, the amount of pure technetium that will be remaining is 12.5 grams
Explanation:
To solve the question, we note that the equation for half life is as follows;
Where:
N(t) = Quantity of the remaining substance = Required quantity
N₀ = Initial radioactive substance quantity = 100 g
t = Time duration = 18 hours
= Half life of the radioactive substance = 6 hours
Therefore, plugging in the values, we have;
Therefore, after 18 hours, the amount of pure technetium that will be remaining = 12.5 grams.
Start by assigning the most complicated species a coefficient of one. That species should contain the greatest number of elements, e.g. .
<em>(not balanced)</em>
Assign coefficients to the rest of the species based on the conservation of atoms. For instance, the left hand side of the equation now contains one atom of hydrogen H and one atoms of chlorine Cl. The left hand side shall have an identical configuration. Both zinc chloride and hydrogen should therefore have a coefficient of 1/2. (Don't panic about the fractions. They are to be eliminated in a few more steps.)
<em>(not balanced)</em>
The coefficient 1/2 in front of zinc chloride indicates the presence of 1/2 zinc atom in the right hand side of the equation. Zinc on the left hand side of the equation should accordingly have a coefficient of 1/2.
Increasing coefficients on both sides of the equation by a factor of two to eliminate all fractions. Hence the balanced equation.
(balanced)
The same set of operations should work for the second equation.
(balanced)
Note that the third equation does not accurately represent the catalytic decomposition of hydrogen peroxide . The balanced equation should be:
(balanced)
Answer:
it is the Sparta ruined Athens’s farmland to try to get Athens to fight on farm land
Explanation:
just did
175.8 g NaCl to moles:
(175.8 g)/(58.44 g/mol) = 3.008 mol NaCl
Molarity = moles of solute/volume of solution in liters
(3.008 mol NaCl)/(1.5 L) = 2.0 M.
The molarity of this solution would be 2.0 M.
Ge and As
they are lined up between the non metals and metals so they are metalloids