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An unknown compound is determined by elemental analysis to have the following composition: Element Mass(%) Cs 66.3 Cl 17.7 O 16.0   What is the compound’s empirical formula?

At which position(s) does the pendulum have maximum kinetic energy?

The reaction NH3(aq) + H2O(l) → OH-(aq) + NH4+(aq) is an example of _____?

Consider 100 g blocks of aluminum (specific heat capacity: 0.897 J/g°C) and iron (specific heat capacity: 0.449 J/g°C). Both blocks are placed on a hotplate such that 1000 J of energy is transferred to each block. What happens to their temperatures?

The specific heat capacity of Styrofoam is 1.131 J/gK. What is the heat capacity of a 3.55 g Styrofoam cup?

Which of the following reactions is written correctly?

A 25.0 g sample of glass (silicon dioxide, specific heat capacity of  sample of 1.05 J/g°C) at 100°C is dropped into a vat of water whose final temperature is 26°C. How much heat does the glass transfer to the water?

A 50.0 g piece of unknown metal at 53.6 °C is placed in 100 g of water at 25.0 °C contained in a coffee-cup calorimeter. The metal and water come to the same temperature at 23.6 °C. According to the following table, what is the likely identity of the metal? metal specific heat capacity (J/gK) Mg 1.020 Fe 0.444 Zn 0.390 Ag 0.240 Pb 0.160

Use the data in the following table to calculate the ΔHrxn of the following reaction: CO2(g) + H2(g) → CO(g) + H2O(g) substance ΔH°f (kJ/mol) CO2(g) −393.51 H2(g) 0 CO(g) −110.52 H2O(g) −241.82

The structure below shows one of the amino acids that make up proteins. What is its nitrogen content expressed in mass percent?