Answer:
b i think
Explanation: sry if wrong
Answer:
1/32 of the original sample
Explanation:
We have to use the formula
N/No = (1/2)^t/t1/2
N= amount of radioactive sample left after n number of half lives
No= original amount of radioactive sample present
t= time taken for the amount of radioactive samples to reduce to N
t1/2= half-life of the radioactive sample
We have been told that t= five half lives. This implies that t= 5(t1/2)
N/No = (1/2)^5(t1/2)/t1/2
Note that the ratio of radioactive samples left after time (t) is given by N/No. Hence;
N/No= (1/2)^5
N/No = 1/32
Hence the fraction left is 1/32 of the original sample.
1. To solve this question, you need to equalize the mass of solute for both solution. The calculation would be:
mass of solute= volume*concentration
mass1=mass2
volume1 * concentration1 = volume2 * concentration2
volume1 * 0.7%= 2L *(1000ml/L) * 0.2%
volume1 = 2000ml * (0.2%/0.7%)
volume1= 571.429 ml
2. Since you already have the volume of stock needed, you just need to subtract it from the total solution volume to count the number of solvents needed.
new solution volume= stock volume + diluting solvent volume
2L * 2000ml/L = 571.429ml + diluting solvent volume
diluting solvent volume= 2000ml- 571.429 ml= 1428.571ml
This is called the Mass Number of the isotope of the atom.
Isotopes are different forms of the same atom. They have the same number of protons but different number of neutrons.
Carbon-12 has mass number 12 as it has 6 protons and 6 neutrons.
Carbon-14 has mass number 14 as its has 6 protons and 8 neutrons.
