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When 13.6 g of calcium chloride, CaCl2, was dissolved in 100.0 mL of water in a coffee cup calorimeter, the temperature rose from 25.00 °C to 31.75 °C. Determine the ∆Hrxn in kJ/mol for the reaction as written below. Assume that the density of the water is 1.000 g/mL, and that the specific heat capacity of the solutions is that of pure water. Must show your work (scratch paper) to receive credit. CaCl2(aq) → Ca2+(aq) + 2 Cl- (aq)                            ∆Hrxn = _________ 

How many electrons, protons, and neutrons are present in the following isotopes   protons: [a], neutrons: [b], electrons: [c]  

Solve the following to the proper number of significant figures: 934 × 0.00435 + 107 =

Solve the following to the proper number of significant figures:(847.89 – 847.73) × 14,673=

The element X has three naturally occurring isotopes. The isotopic masses (amu) and % abundances of the isotopes are given in the table below. The average atomic mass of the element is ________ amu.             Isotope Abundance (%) Mass 164X 30.60 159.37 164X 15.79 162.79 164X 53.61 163.92  

How many electrons, protons, and neutrons are present in the following isotopes  protons: [a], neutrons: [b], electrons: [c] 

How many grams of hydrogen gas would be produced when 6.0 grams of magnesium react with excess of an acid?   Mg + 2 HCl → MgCl2 + H2    

How many grams of water will be required to completely react with 1.00 mol of CaO according to the following reaction?   CaO + H2O → Ca(OH)2  

The following reaction: LiOH + HCl → LiCl + H2O, is an example of

How many moles of NH3 will be produced when 1.60 mol of N2 react with excess of hydrogen gas according to the following reaction?   N2 + 3 H2 → 2 NH3