One way to cool a cup of coffee would be to plunge an ice-cold piece of aluminum into it. Suppose 20.00 g piece of aluminum is stored in the refrigerator at 0.0 °C and then dropped into a cup of coffee. The coffee's temperature drops from 90.0 °C to 75 °C. How many kJ of thermal energy did the piece of aluminum absorb? (Specific heat = 0.902 J/g* °C)

Answer asap need it by wednesday morning carry out the following calculations on ph and ka of from data. i. calculate the ph of 0.02m hcl ii. calculate the ph of 0.036m naoh iii. calculate the ph of 0.36m ca(oh)2 iv. calculate the ph of 0.16m ch3cooh which has ka = 1.74 x 10-5 mol dm-3 v. calculate ka for weak acid ha which has a ph of 3.65 at 0.30m concentration vi. calculate the ka of a solution made by mixing 15.0 cm3 0.2m ha and 60.0 cm3 0.31m a-. [ph= 3.80] vii. calculate the ph of a solution made by mixing 15.0 cm3 0.1m naoh and 35.0 cm3 0.2m hcooh. [ka = 1.82 x 10-4 m]

The equation picture below shows which type of nuclear reaction u 235 + n x e 134 + sr 100 + 2n

If you burn 46.6 g of hydrogen and produce 416 g of water, how much oxygen reacted