A 25.5-g aluminum block is warmed to 65.4$^{\circ} \mathrm{C}$ and plunged into an insulated beaker containing 55.2 g water initially at 22.2$^{\circ} \mathrm{C}$. The aluminum and the water are allowed to come to thermal equilibrium. Assuming that no heat is lost, what is the final temperature of the water and aluminum?

Top fuel dragsters and funny cars burn nitromethane as fuel according to the balanced combustion equation: $2 \mathrm{CH}_{3} \mathrm{NO}_{2}(l)+3/2 \mathrm{O}_{2}(g) \longrightarrow 2 \mathrm{CO}_{2}(g)+3 \mathrm{H}_{2} \mathrm{O}(l)+\mathrm{N}_{2}(g)$ $\Delta H_{\mathrm{rxn}}^{\circ}=-1418 \mathrm{kJ}$ The enthalpy of combustion for nitrom ethane is - 709.2 kJ / mol. Calculate the standard enthalpy of formation ($\Delta H_{\mathrm{f}}^{\circ}$) for nitromethane.

Compare. Write <, =, or >. 3 _____ -6

The website forsalebyowner.com reported that total real estate commissions in 2007 were $55 billion, an increase of $19 million over the year 2000. What was the percent increase?

Palmitic acid $(C_{16}H_{32}O_2)$ is a dietary fat found in beef and butter. The caloric content of palmitic acid is typical of fats in general. Write a balanced equation for the complete combustion of palmitic acid and calculate the standard enthalpy of combustion . What is the caloric content of palmitic acid in Cal/g? Do the same calculation for table sugar (sucrose, $C_{12}H_{22}O_{11}$). Which dietar y substance (sugar or fat) contains more Calories per gram? The stand ard enthalpy of formation of palmitic acid is -208 kJ/ mol and that of sucrose is - 2226.1 kJ/mol. [Use $H_2O(l)$ in the balanced chemical equations because the metabolism of th ese compounds produces liquid water.]

Determine the possible number of positive real zeros and negative real zeros for each polynomial function given by Descartes' Rule of Signs. $P(x)=6 x^{4}-x^{3}+5 x^{2}-x+9$

If the top 500 m of ocean water increased in temperature from $17^{\circ} \mathrm{C} \text { to } 18^{\circ} \mathrm{C}$, what would be the resulting rise in ocean height? A. 0.11 m B. 0.22 m C. 0.44 m D. 0.88 m

Discuss the advantages and disadvantages of fusion power from the standpoints of safety, pollution, and resources.

The file Mobile Commerce contains the mobile commerce penetration values, the percentage of the country population that bought something online via a mobile phone in the past month, for 24 of the world's economies. Are the data skewed? If so, how?

Write a short description of the motion of a real object for which Figure mentioned would be a realistic position-versus-time graph.

How is thermal energy transferred between two object of different temperature?

A near-sighted person might correct his vision by wearing diverging lenses with focal length f = -50 cm. When wearing his glasses, he looks not at actual objects but at the virtual images of those objects formed by his glasses. Suppose he looks at a 12-cm-long pencil held vertically 2.0 m from his glasses. Use ray tracing to determine the location and height of the image.

Write an equation relating the rates of change of the variables in these formulae.

Volume of a cone: $V=\frac{1}{3} \pi r^2 h$

Describe how the distribution of Russia's natural resources makes utilizing them difficult.