What is the average atomic mass for a sample of Carbon isotopes if there are 20 Carbon-13 isotope, 15 Carbon-14 isotopes and 50 Carbon-12 isotopes. 20
Hint: Calculate the percentage of each isotope first !

Based on its chemical properties, identify the position of each chemical family on the periodic table.

What state of matter is ice a. liquid b. element c. solid d. gas

For a research project, a student decided to test the effect of the lead(ii) ion (pb2+) on the ability of salmon eggs to hatch. this ion was obtainable from the water‐soluble salt, lead(ii) nitrate, which the student decided to make by the following reaction. pbo(s) + 2 hno3(aq) → pb(no3)2(aq) + h2o losses of product for various reasons were expected, and a yield of 86.0% was expected. in order to have 5.00 g of product at this yield, how many grams of pbo should be reacted? (assume that sufficient nitric acid, hno3, would be used.)