Which student is determining the atomic mass of sodium (Na)? A.
Cheryl finds the average mass of sodium isotopes found in nature
B.
Abu counts the number of neutrons in an isotope of sodium
C.
Maria adds the number of protons to the number of neutrons in sodium atoms
D.
Jerry counts the number of protons in sodium atoms found in nature

Which statement is true about hcl? (5 points) select one: a. it is a salt because it increases the concentration of metallic ions. b. it is a salt because it is formed by the reaction of an acid and a base. c. it is an acid because it increases the concentration of hydroxyl ions. d. it is an acid because it increases the concentration of hydronium ions.

Consider the four elements above. which one of these elements will combine with oxygen in a 1: 1 ratio?

Lab reagent, hypothesis test. a reference solution used as a lab reagent is purported to have a concentration of 5 mg/dl. six samples are taken from this solution and the following concentrations are recorded: (5.32, 4.88, 5.10, 4.73, 5.15, 4.75) mg/dl. these six measurements are assumed to be an srs of all possible measurements from solution. they are also assumed to have a standard deviation of 0.2, a normal distributin, and a mean concentration equal to the true concentration of the solution. carry out a significance test to determine whether these six measurements provide reliable evidence that the true concentration of the solution is actually not 5 mg/dl.