Scientists who do carbon 14 dating use 5700 years for its half life. find the age of a sample in which 10% of the radioactive nuclei originally present have decayed

For this problem, we use the formula for radioactive decay which is expressed as follows:

An = Ao (e^-kt)

where An is the amount left after time t, Ao is the initial amount and k is a constant determined experimentally. 
First, we calculate for the value of k from the data we have of the half life. We do as follows:

An = Ao (e^-kt)
0.5 = e^-k(5700)
k = 1.21x10^-4 / year

After solving for k, we can use this value to solve for the age of the sample given the percent of the carbon nuclei that is remained after that particular time,

An = Ao (e^-kt)

An/Ao = e^-kt
1 - .10 = e^-1.21x10^-4(t)
t = 878.00 years

a  solution  is always transparent, light passes through with no scattering from solute particles which are molecule in size. the  solution  is homogeneous and does not settle out. a colloid is intermediate between asolution  and a  suspension. while asuspension  will separate out a colloid will not.

nacl or sodium chloride is an ionic compound. this is because an ionic compound pertains to a compound that consists of positively and negatively charged ions. in this case, na (sodium) has a tendency to lose one electron when it reacts with with other atoms, so the resulting sodium ion contains 11 protons and 10 electrons, thus making it positively charged (na+), when chlorine reacts, it usually gains one electron to form an ion called chloride, thus making it negatively charged ( since the ions are oppositely charged, they attract.