To understand how to measure using a graduated cylinder, triple beam balance and a ruler Objective of the day:
Daily Question # 1 What is the volume measurement in the following diagram?
Back to the Basics
Science Lab Equipment
Graduated Cylinder Measure about 26.1 mL
Scale Weigh the object
Ruler Measure the length of the object
SI Units International System of Units (SI)
Metric Prefixes
BIGGER SMALLER
k kilo h hecto dk deca BASE (m, g, L) d deci c centi m milli BIG SMALL
1.Determine whether you are going up the ladder or down the ladder. If you go up, move the decimal to the left. If you go down, move the decimal to the right. 2.Use the ladder to determine how many places to move the decimal. The number of steps on the ladder is equal to the number of decimal places. 3.Write the correct units with your answer. How do you convert between metric units?
Practice Problems mg = ____________ g cm = ______________ m ,000 ng = ____________ g mm = _______________ μm
Dimensional Analysis Convert 892cm to meters…… ①Find the conversion factor 1)What unit is bigger? (This will have the value of 1) 2)What unit is smaller (This will have the big number) 3)What is the difference between them (Count how many you pass on the chart, each one is 10 1 more) ②Make the units cancel to get the units you want
Conversions ①3.46 cg = _____ mg ②1.00 km = _____ cm ③1470 mg = ______ μg ④15.5 ng = _____ dg ⑤100 cm = ______ pm
Conversions ①8.9g/cm = _______ kg/m ②4.23m/L = _______ cm/mL ③19.6cm/L = ______ m/mL ④2.5g/m = ______ g/cm
Scientific Notation Method of writing very small or very large numbers – A positive exponent means the decimal moved to the left. A negative exponent means the decimal moved to the right
Scientific Notation 602,200,000,000,000,000,000,000 = ? – Step 1: Make the Coefficient less than 10 and more than 1. – Step 2: Find out how many places over the decimal has to move to give you the number in step 1.
Scientific Notation ①5,300,000 = ? ②4,302,000,000 = ? ③-24,500 = ? ④ = ? ⑤ = ?
Scientific Notation ①5.3 x 10 4 = ? ②7.02 x 10 8 = ? ③-3.21 x 10 3 = ? ④7.093 x = ? ⑤-5 x 10 -3
Scientific Notation Addition and Subtraction: 1)Make the exponents the same number 2)Add/Subtract the coefficient 5.3x x10 3 = 5.3x x10 2 = 31.3x10 2 = 3.13x10 3
Scientific Notation Multiplication and Division 1)Add or Subtract exponents 2)Multiply or Divide coefficients MultiplyDivide 5.2x10 2 x 4.8x10 4 =5.0x10 4 ÷ 2.5x10 3 = (5.2 x 4.8) x10 (2 + 4) (5.0 ÷ 2.5) x10 (4- 3) = 24.96x x x10 7
Scientific Notation ①5.6x x10 2 = ? ②4.0x10 6 – 8.3x10 5 = ? ③2.3x10 5 x 4.3x10 6 = ? ④8.2x10 12 ÷ 4.1x10 7 = ?
Derive a relationship between the following 17 = = = = = = 4
Accuracy vs. Precision Accuracy: How close to the real value Precision: How close a series of measurements are to each other
Significant Figures – Rounding Numbers: -Round up if the digit to the right is between Drop the number to the right if it’s between 3.8 Significant Figures Tell You What Number To Round To!
Significant Figures All Non-zero numbers (1,2,3,4,5,6,7,8,9) are significant Zeros – 1)Front of number are NEVER significant , 0.42, all have 2 sig. figs 2)Middle of number are ALWAYS significant 7003, 40.79, all have 4 sig. figs 3)End are SOMETIMES significant At end AFTER decimal, ALWAYS significant 36.00, 1.010, all have 4 sig figs At end BEFORE decimal, NEVER significant 300, 7000, all have 1 sig fig
Significant Figures ①5.30 = ? ② = ? ③1900 = ? ④ = ?
Significant Figures Addition and Subtraction – Match the number with the least number of decimals Ex: = = = 17 Multiplication and Division – Match value with fewest number of sig figs Ex:2.00 x 11 = x 11.0 = x 11 = 20