Which equation represents a neutralization reaction?
A) Na2CO3 + CaCl2 - 2NaCl + CaCO3
B) Ni(NO3)2 + H2S - NiS + 2HNO3
C) NaCl + AgNO3 - AgCl + NaNO3
D) H2SO4 + Mg(OH)2 - MgSO4 + 2H2O

Why are pipes bursting in the in extremely cold weather?

Sally is making a model of a magnesium atom with an atomic mass number of 24 for her chemistry class. she has foam balls for the protons, neutrons, and electrons. she has added 6 neutrons to her model so far. how many more neutrons does she need to add to complete her neutral atom of magnesium?

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.