The tool to measure the liquid is a measuring cylinder.
Radioactive decay => C = Co { e ^ (- kt) |
Data:
Co = 2.00 mg
C = 0.25 mg
t = 4 hr 39 min
Time conversion: 4 hr 39 min = 4.65 hr
1) Replace the data in the equation to find k
C = Co { e ^ (-kt) } => C / Co = e ^ (-kt) => -kt = ln { C / Co} => kt = ln {Co / C}
=> k = ln {Co / C} / t = ln {2.00mg / 0.25mg} / 4.65 hr = 0.44719
2) Use C / Co = 1/2 to find the hallf-life
C / Co = e ^ (-kt) => -kt = ln (C / Co)
=> -kt = ln (1/2) => kt = ln(2) => t = ln (2) / k
t = ln(2) / 0.44719 = 1.55 hr.
Answer: 1.55 hr
Answer:
D
Explanation:
The answer is D. I'm not sure that it is a solid. I don't think it is a ppte, which is the only way it can be a true solid. It is ionic if the reaction is taking place in water and there is someway to start the reaction. Be that as it may, the internal balace numbers of the chemical produced is the only possible answer. The balanced eq;uatioon is
2Al + 3Br2 ==> 2AlBr3
Answer:
moles Ar in 20g = 0.500 mole Ar
Explanation:
moles = grams given / formula weight = 20g / 39.948g·mol⁻¹ = 0.500 mole Ar
Answer:
2.03125g of acetylene
Explanation:
First thing's first, we have to write out the balanced chemical equation;
CaC2(s) + 2H2O(l) → Ca(OH)2(aq) + C2H2(g)
Water is in excess, so CAC2 is our limiting reactant. i.e it determines the amount of product that would be formed.
1 mol of CaC2 produces 1 mol of C2H2
In terms of mass;
Mass = Number of moles * Molar mass
where the molar mass of the elements are;
Ca = 40g/mol
C = 12g/mol
H = 1g/mol
CaC2 = 40+ (2*12) = 64g/mol
C2H2 =( 2 * 12) + ( 2 * 1) = 26g/mol
64g (1 * 64g/mol) of CaC2 produces 26g ( 1mol * 26g/mol) of C2H2
5g would produce x?
64 = 26
5 = x
Upon solving for x we have;
x = (5 * 26) / 64
x = 2.03125g
