HW Questions Unit 1 A.4 A.5 A.6

Homework Questions: Chemistry 

By Kelly Moran

pg. 47

6.) a.) First you pour the cookie mix into a bowl and then you pour in two eggs and then you put in a spoonful of water and oil. Afterwards you mix the ingredients and put the mix on a cookie sheet and pop in the oven and afterwards you're done.

    b.) All the steps are physical changes except when you put the cookie mix in the oven and the dough rises. That's a chemical change.

7.) Substance is an element or a compound. Two examples of a substance are oxygen and water.

8.) a.) Compound 

     b.) Elements 

     c.) Compound 

     d.) Elements  

     g.) Compound

     f.)  Compound 

9.) a.) i and ii represent elements.

     b.) iii, iv, v, and vi represent compounds. 

10.) A chemical formula tells you what elements are in a compound and how many atoms of each element are in the compound. 

11.) Chemical symbols indicate elements of the formula and chemical formulas indicate compounds. 

Concept Check 

1.) We haven't done this experiment yet. 

2.) 

3.) 

pg. 38

1.) a.) Phosphorus 

     b.) Nickel

     c.) Copper

     d.) Cobalt

     e.) Bromine

     d.) Potassium 

     g.) Sodium

     h.) Iron

2.) Phosphorus, Nickel, Cobalt, and Bromine.

3.) Element's symbols are the same everywhere.

4.) a.) Oxygen (2 atoms) , Hydrogen (2 atoms) 

     b.) Calcium (1 atom), Chlorine (2 atoms)

     c.) Sodium (1 atom), Hydrogen (1 atom), Carbon (1 atom), Oxygen (3 atoms)

     d.) Hydrogen (2 atoms), Sulfur (1 atom), Oxygen (4 atoms) 

5.) 2H   + O   = 2H  O

          2        2        2