General Chemistry Answers

Calculate the number of moles of NH₃ present in 100 g of NH₃

of the following statements about different elements are true except

Potassium is an alkali metal. Selenium is a metalloid.

Magnesium is an alkaline earth metal. Iodine is a halogen.

Xenon is a noble gas.

give one advantage of using nano particles in sun creams

Explain the chemistry behind the buffer system in blood.

The isotope strontium-90 is produced during the testing of nuclear weapons. If 100.0mg of strontium-90 was released in the atmosphere in 1960, how much of the radioisotope remains 85 years later? The half-life of strontium-90 is 29 years. Show all your work.

1.Calculate the freezing point of solution containing 0.600 kg of CHCl3 and 42.0 g of Eucalyptol (C10H18O) , a fragrant substance found in the leaves of eucalyptus tree. Kf for CHCl3 is 4.68°C/molal and normal freezing point is -63.5°C.

1.Calculate the freezing point of solution containing 0.600 kg of CHCl3 and 42.0 g of Eucalyptol (C10H18O) , a fragrant substance found in the leaves of eucalyptus tree. Kf for CHCl3 is 4.68°C/molal and normal freezing point is -63.5°C.

2.List the following aqueous solutions in order of their expected freezing points ( from lowest to highest) : 0.50 m CaCl2 ; 0.15 m NaCl ; 0.10 m HCl ; 0.050 m HC2H3O2 ; 0.10 m C12H22O11. Then explain the reason why you arrange it that way.

List the following aqueous solutions in order of their expected freezing points ( from lowest to highest) : 0.50 m CaCl2 ; 0.15 m NaCl ; 0.10 m HCl ; 0.050 m HC2H3O2 ; 0.10 m C12H22O11. Then explain the reason why you arrange it that way.

Calculate the solubility of Ca(OH)₂ in a 0.469M CaCl₂ solution at 31⁰C, given that the K_sp of Ca(OH)₂ is 4.96 X10^-6 at that temperature and give the answer in milli Molar units.