Ch2 rev ans
paper graduate etc is on test
p57 (e55)
4a. 53.88g b. 77m2 c. 3.159g/mL
5 a 3.01 *10-1g . b. 6.967 *109g . c. 3.21* 101m2 . d. 4.32 *10-8g/mL
steps of scientific method and what they mean- observations with senses; problem is question to be answered; hypothesis is possible solution to problem that is tested by the experiment; conclusion is a summation of what was learned resulting in a model or theory in our mind; that model can be used to make predictions
2 types of observation and their difference- quantitative = measurements, qualitative = everything else
equivalents for kilometer = 1000m, meter=100cm, millimeter= .001m, milliliter = cubic centimeter, lite = 100mL, cubic decimeter = IL
difference between mass and weight- mass amount of matter, weight force of gravity; weight is not conserved
difference between precision and accuracy. see dart targets in text
how many Sig figs? 1000 =1, 10.0 =3 , 275 =3 , 101020 =5 265.80 =5 0.0058 =2
how many digits in answer - density if mass is12.84g and vol is 8.2mL - 2
what are some density units? g/mL , kg/m3, anything with mass over volume
Give an example of derived units. volume, density, etc. made of more than one base unit
Find the density in g/mL of an object that is 3kg and 60mL; answer must be in g/mL, 3000g/60mL= 50g/mL
What conversion factor would you use to change 45cm to m? 1m/100cm
How do you find volume by displacement? put in water and see how much water goes up
Scientific notation change 4.58 *10 –4 = 0.000458 and 45,000,000,000 = 4.5 *1010
Multiply = 2.1*105 and divide = 1.0 *10-14 the numbers above use sci notation
What is the density of water? 1g/mL How does oil compare? oil is less
Find the density (use sig figs)of block 2.5 * 3.1* 12.2cm if its mass is 125.68g. Float? m/94.55 cc= 1.3g/cc, sink
Find density(use sig figs) (empty graduate 46.89g, graduate with liquid is 58.12g (see picture )
d= m/v = 11.23g/56.0mL = .201g/mL
Ch2 rev ans