A 50.8g sample of glass, which has a specific heat capacity of 0.670·J·g?1°C?1, is put into a calorimeter (see sketch at right) that contains 150.0g of water. The temperature of the water starts off at 22.0°C. When the temperature of the water stops changing it's 25.6°C. The pressure remains constant at 1atm. Calculate the initial temperature of the glass sample. Be sure your answer is rounded to the correct number of significant digits.

Consider three unlabeled bottles, each contain small pieces of one of the following metals. - magnesium - sodium - silver the following reagents are used for identifying the metals. - pure water - a solution of 1.0 molar hcl - a solution of concentrated hno3 (a) which metal can be easily identified because it is much softer than the other two? describe a chemical test that distinguishes this metal from the other two, using only one of the reagents above. write a balanced chemical equation for the reaction that occurs. (b) one of the other two metals reacts readily with the hcl solution. identify the metal and write the balanced chemical equation for the reaction that occurs when this metal is added to the hcl solution. use the table of standard reduction potentials (attached) to account for the fact that this metal reacts with hcl while the other does not. (c) the one remaining metal reacts with the concentrated hno3 solution. write a balanced chemical equation for the reaction that occurs. (d) the solution obtained in (c) is diluted and a few drops of 1 m hcl is added. describe what would be observed. write a balanced chemical equation for the reaction that occurs.

A40 kilogram skier starts at the top of a 12 meter high slope. at the bottom, she is travelling 10 meters per second. how much energy does she lose to friction

The empirical formula of a compound is ch2o and its mass is 120 amu/molecule, what is its formula?