A river passing an industrial plant is suspected of being polluted with lead nitrate (Pb(NO3)2). A method to determine the presence of the substance is to perform a precipitation reaction in which ions displace each other forming an insoluble precipitate. Design an investigation to determine how the distance from the industrial plant influences the colour and amount of precipitate formed when magnesium sulphide (MgS) is added to a river sample.

the answer is 1260

you spend 7 hours in school for 1 school day with 5 school days in 1 school week with 36 school weeks in a school year.

7*5*36= 1260 it's all about multiplying

percent abundance for cu-63 can be shown as:

63 x + 65 (1-x) = 62.9296

65 - 62.9296 = 2 x

x = 1.035

thus, percent abundance for cu-63 is 1.035

percent abundance for cu-65 can be shown as:

63 x + 65 (1-x) = 64.9278

65 - 64.9278 = 2 x

x = 0.0361

thus, percent abundance for cu-63 is 0.0361

the mass spectrum of cu-63 showing the intense peak as, this isotope is found in nature more abundantly around 92.38 % in comparison to cu-65 which is found 62.58 % naturally

the correct answer would be b) volume versus temperature, because they are also directly proportional.