A piece of copper with a mass of 75.6 g has an initial temperature of 65.4oC. The piece of copper is immersed in a beaker containing an unknown mass of water at 22.7 C. When the two substances reach thermal equilibrium, the final temperature is 24.2 C. What is the mass of the water, g? Specific heat of Cu = 0.385 J/g ·oC, The specific heat of H2O is 4.184 J/g ·oC

What are the coefficients for the following reaction when it is properly balanced?  __Zn(s)+ __HNO3(aq) –>  __Zn(NO3)2 (aq) + __NO2(g) + __H2O(l)

This bonus question is worth 4 points and is set to 0 points in Canvas. If correct, I will add the points to your overall grade after review. Skipping it will not affect your Test 3 grade. Bonus 2 A 42.0 L steel tank at -15.0 °C contains ammonia gas, NH₃, at a pressure of 980 mmHg. How many grams of NH₃ are in the tank? R = 0.0821 L·atm·mol⁻¹·K⁻¹ Molar mass of NH₃ = 17.03 g/mol 1 atm = 760 mmHg

Find the ΔH for the reaction below, given the following reactions and subsequent ΔH values:PCl5(g)  →  PCl3(g)  +  Cl2(g) P4(s)  +  6Cl2(g)  →  4PCl3(g)            ΔH = -2439 kJ4PCl5(g)  →  P4(s)  +  10Cl 2(g)         ΔH = 3438 kJ

Identify the ionic compound.

How much heat in kJ is produced by the combustion of 88.0 g of propane (C₃H₈)? C₃H₈(g) + 5O₂(g) → 3CO₂(g) + 4H₂O(g); ΔH°rxn = −2220 kJ The molar mass of propane is 44.10 g/mol.

A 44.8 g rhodium Rh sample contains how many rhodium atoms? 1 mol = molar mass (g/mol) 1 mol = Avogadro number = 6.02 x 1023 Molar mass Rh 102.9 g/mol

How much heat in kJ is produced by the combustion of 155 g of ethanol (C2H6O)? C2H6O(g) + 3O2(g)  → 2CO2(g) + 3H2O(g);       ∆H°rxn=−1366.8 kJ/mol The molar mass  of ethanol is 46.07 g/mol  

Calculate the molecular mass of an unknown gas at a temperature of 18.0°C. A sample of 9.880 g occupies 3,200. mL at 812 torr. R = 0.08206 L·atm/mol·K; 1 atm = 760 torr; 1 L = 1000 mL

What is the molar (M) concentration of phosphate ions (PO43-) in a 725 mL solution containing 155 grams of lead(III) phosphate, Pb3(PO4)4? Molar mass of Pb3(PO4)4 is 1001.4 g/mol