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A 15.0 g sample of aluminum metal at 25.0°C is heated by the addition of 315 J of energy. What is the final temperature of the aluminum in °C? (Specific heat capacity of aluminum = 0.903 J/g·K)

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

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 1 Use the standard enthalpy of formation (ΔH°f) values and the standard enthalpy of reaction (ΔH°rxn) given below to calculate the standard enthalpy of formation of CO(g). 2 CO₂(g) + 2 H₂(g) → 2 CO(g) + 2 H₂O(g)  ΔH°rxn = +82 kJ ΔH°f values: CO₂(g): −394 kJ/mol H₂O(g): −242 kJ/mol What is ΔH°f for CO(g)?

Use the Lewis dot structure (make sure you show all electron pairs) and VSEPR theory to predict the molecular geometry and bond angles in the molecule of SO₂. Hint: Use the Table below to answer the question.   VSEPR quick reference: electron groups, shapes, and approximate bond angles Electron Groups Bonding Groups Lone Pairs Electron Geometry Molecular Geometry Approximate Bond Angles 2 2 0 Linear Linear 180° 3 3 0 Trigonal planar Trigonal planar 120° 3 2 1 Trigonal planar Bent

A  8.50 g sample of copper metal at 22.0°C is heated by the addition of 155 J of energy. The final temperature of the copper is ________°C. The specific heat capacity of copper is 0.38 J/gK  

According to the octet rule, a Bromine (Br) atom has a tendency to _____.

Calculate the ∆H°rxn for the combustion of methane using the given ∆H°f. CH4 (g)  +  2O2(g)  → CO2(g) + 2H2O(l) ∆H°f, methane(g) = -74.60 kJ/mol ∆H°f, water(l) = -285.8 kJ/mol ∆H°f, carbon dioxide(g) = -393.5 kJ/mol

Determine the mass of an object that has a volume of 21.60 mL and a density of 1.98 g/mL. Pay attention to significant figures!

Use the Lewis dot structure (make sure you show all electron pairs) and VSEPR theory to predict the molecular geometry and bond angle in the ammonium ion NH4+. Hint: Use the table below to answer the question.   VSEPR quick reference: electron groups, shapes, and approximate bond angles Electron Groups Bonding Groups Lone Pairs Electron Geometry Molecular Geometry Approximate Bond Angles 2 2 0 Linear Linear 180° 3 3 0 Trigonal planar Trigonal planar 120° 3 2 1 Trigonal planar Bent

Give the number of valence electrons for CO32-.