Joules (J) are a measure of energy.  Chemists often measure energy in calories (cal).  If 1 cal = 4.184 J, how many cal are equivalent to 48.3 J?

If 0.066 mol of hydrochloric acid (HCl) is mixed with 0.066 mol of sodium hydroxide (NaOH) in a "coffee cup" calorimeter, the temperature of 5.0 g of the resulting solution increases from 25.0°C to 30.0°C.  Given that the energy released is 1.2 × 101 cal when the specific heat of the resulting solution is 1.00 cal/g−°C, use a conversion factor to convert the energy released to joules (J).  Enter your answer in scientific notation. Be sure to answer all parts.

The nutritional calorie (Calorie) is equivalent to 1 kcal. One pound of body fat is equivalent to about 4.1 x 10³ Calories. If an athlete expends (1950 kJ/h), how long does it take her to work off 1.0 lb of body fat?

A chemist carefully measures the amount of heat needed to raise the temperature of a 0.29 kg sample of a pure substance from -2.6 °C to 18.9 °C. The experiment shows that 2.8 kJ of heat are needed. What can the chemist report for the specific heat capacity of the substance? Round your answer to 2 significant digits. - 1 1 ·K

The heat involved in a temperature change can be calculated using the following equation. Q (heat) = m(mass) x C(specific heat capacity) x ΔT (change in temperature). Jonathan was running a test in the lab to find out how many calories of energy it would take to heat up a piece of iron. He held the iron in a flame for 1 minute. He immediately placed the iron in 50.0 grams of water that had a temperature of 20oC. He used a thermometer in the water and watched it closely. The thermometer showed the temperature of the water rising and it peaked at 24oC. How much heat did the iron metal transfer to the water? The specific heat capacity of water is 1.00 cal/g-Co

A 1401 kg1401 kg car is traveling down the road at 85.8 km/h.85.8 km/h. While traveling at this rate of speed, what is the kinetic energy of this vehicle in kilojoules?

Expressing amounts of energy in different energy units is necessary to solve many chemistry problems. For practice, complete the following table. The Joule (J) is the SI unit of energy. 1 calorie (cal) = 4.184 J; 1 kcal = 1000 cal J kJ kcal 549       0.684       0.226

Consider these reactions, where M represents a generic metal. 1. 2 M(s) + 6 HCI(aq) 2 MCI, (аq) + 3 Н, (2) AH1 = -556.0 kJ 2. HCl(g) HCl(aq) AĦ2 = -74.8 kJ 3. H, (g) + Cl, (g) → 2 HCI(g) ΔΗ = -1845.0 kJ 4. MCI, (s) – MCI, (aq) AĦ4 = -493.0 kJ Use the given information to determine the enthalpy of the reaction 2 M(s) + 3 Cl, (g) – - 2 MCl, (s) -556.0 ΔΗ- Incorrect

The specific heat of a substance is the amount of heat required to raise the temperature of one gram of the substance by one degree Celsius. The relationship between the amount of heat gained or released by a substance and the change in temperature of the substance is given by the equation ?=??Δ?q=m⁢s⁢Δ⁢T where ?q is the heat gained or released, ?m is the mass of the substance, ?s is the specific heat of the substance, and Δ?Δ⁢T is the change in temperature. 1. Rearrange the equation to solve for ?. 2. When a substance with a specific heat of 0.635 J/g⋅∘C0.635 J/g⋅∘C is heated from 25.2 ∘C25.2⁢ ∘C to 71.4 ∘C,71.4⁢ ∘C, it absorbs 422 J422 J of heat. Calculate the mass of the substance.

Group I Cations of 6 M HCI; centrifuge for ~1 minute. Decant the solution and add an additional one or two drops of 6 M HCI; if no additional precipitate forms, the precipitation is complete. If it was incomplete, centrifuge to obtain the additional solid; then decant the liquid, add 1 or 2 drops of 6 M HCI, and repeat the procedure until no precipitate forms. Discard the supernatant into the appropriate waste container or keep for later experiments if your instructor so indicates. Add 1.5 mL of cold deionized or distilled water to the precipitate to wash; agitate, centrifuge, and discard the water to the appropriate waste container. Repeat the wash procedure. The solid contains Pb2*, Ag*, and/or Hg22*. Step 2. Separation of Pb2*. Add 1 mL of boiling water to the solid from step 1. Agitate, centrifuge, and decant the liquid. Repeat the extraction, combining the supernatant. The liquid should contain Pb?* if any is present. Step 3. Testing for Pb2*. Add 2 or 3 drops of 0.2 M K2CRO4…