Answer: 20 mg Te-99 remains after 12 hours.
Explanation: N(t) = N(0)*(1/2)^(t/t1/2)
N(t) = (80 mg)*(0.5)^(12/6)
N(t) = 20 mg remains after 12 hours
Answer:
<em><u>To determine the number of significant figures in a number use the following 3 rules:</u></em>
<em><u>To determine the number of significant figures in a number use the following 3 rules:Non-zero digits are always significant.</u></em>
<em><u>To determine the number of significant figures in a number use the following 3 rules:Non-zero digits are always significant.Any zeros between two significant digits are significant.</u></em>
<em><u>To determine the number of significant figures in a number use the following 3 rules:Non-zero digits are always significant.Any zeros between two significant digits are significant.A final zero or trailing zeros in the decimal portion ONLY are significant.</u></em>
Hope this helps!
https://youtu.be/MT5tKijKZwQ
Answer:
Extensive or inextinsive and either physical or chemical
<span>Mass of the solution = 0.17m
Kb for C6H5NH2 = 3.8 x 10^-10
We know Ka for C6H5NH2 = 1.78x10^-11
We have Kw = Ka x Kb => Ka = Kw / Kb
=> (C2H5NH2)(H3O^+)/(C2H5NH3^+) => 1.78x10^-11 = K^2 / 0.17
K^2 = 3 x 10^-12 => K = 1.73 x 10^-6.
pH = -log(Kw(H3O^+)) = -log(1.73 x 10^-6) = 5.76</span>
