1 Which scientist first said that "elements are made up of identical atoms

which cannot be created or destroyed"?

Bohr

Democritis

Thomson

O

Dalton

Other:

A generic solid, X, has a molar mass of 78.2 g/mol. In a constant-pressure calorimeter, 12.6 g of X is dissolved in 337 g of water at 23.00 °C. X (s) yeilds X (aq) The temperature of the resulting solution rises to 24.40 °C.

A probe sent to the planet mercury has measured the electronegativities of several elements it has detected on the planet. element 1 2 3 4 5 electronegativity, χ 2.58 1.88 2.10 2.60 3.16 which element would you expect to identify as a metal?

Classify each of the following colloids as either an aerosol, a foam, an emulsion, a sol, a gel, or a solid sol. Example Colloid Type (a) Dust (b) Mud (c) Styrofoam

Identify the information that can be included in a chemical equation.

Reflections-magnesium metal burns with a bright white flame. what conclusions can you draw about the electron transitions that can take place for a magnesium atom?

The study of matter and the changes that occurs in matter

Which would be a good source to find weather information about your town from last month? reference book about weather old copies of local newspapers a magazine with weather articles

What is the difference between a mixture, compound, element and pure substance

It takes 554 kJ to remove one mole of electrons from the atoms at the surface of a solid metal. How much energy does it take to remove a single electron from an atom at the surface of this solid metal?

What is the name for a substance formed in a chemical reaction?