Which of the following is correct concerning subatomic particles? a) the electron was discovered by goldstein in 1886. b) the neutron was discovered by chadwick in 1932. c) the proton was discovered by thomson in 1880. d) cathode rays were found to be made of protons. how many neutrons and protons does a neutral atom of sodium with an atomic mass number of 23 have? a) 22 neutrons; 11 protons b) 23 neutrons; 11 protons c) 11 neutrons; 11 protons d) 12 neutrons; 11 protons

Who is better, messi or cristiano, i need this for a chemistry class. asap

11. phosphorus-32 is radioactive and has a half life of 14 days. how much of a 124 mg sample of phosphorus-32 is present after 56 days? a) 7.75 mg b) 15.5 mg c) 31.0 mg d) 62.0 mg

7. using your knowledge of colligative properties explain whether sodium chloride or calcium chloride would be a more effective substance to melt the ice on a slick sidewalk. use 3 – 4 sentences in your explanation. 8. when a 2.5 mol of sugar (c12h22o11) are added to a certain amount of water the boiling point is raised by 1 celsius degree. if 2.5 mol of aluminum nitrate is added to the same amount of water, by how much will the boiling point be changed? show all calculations leading to your answer or use 3 – 4 sentences to explain your answer. 9. if 5.40 kcal of heat is added to 1.00 kg of water at 100⁰c, how much steam at 100⁰c is produced? show all calculations leading to an answer. 10. the freezing of water at 0⁰c can be represented as follows: h2o (l) ↔ h2o(s) the density of liquid water is 1.00 g/cm3. the density of ice is 0.92 g/cm3. in 3 – 4 sentences explain why applying pressure causes ice to melt.