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Mass and Volume Mass DEFINITION: Mass is how much matter is in an object. MASS OF A SOLID To calculate the mass of a solid, use a triplebeam-balance. Before you place the solid on the triple beam balance, make sure it is zeroed. If it isn’t, use the knob on the left to adjust it. Now all you need to do is place the solid on the balance and adjust the sliders, starting with the biggest one. Make sure they click into place! Once the pointer is realigned to zero, add up all the numbers. Now you have the mass of your solid. The unit of measure for the mass of solids is grams (g). Mass Click on the picture to play with a really animation about the triple beam balance! cool MASS OF A LIQUID Mass Since you cannot pour the liquid directly on to the triple-beam-balance, measuring the mass of a liquid is slightly more complicated. First you need to find the mass of a container, such as a beaker or a graduated cylinder. Record the mass. Next, pour the liquid into the container and take the mass. To find the mass of the liquid, subtract the mass of the container from the mass of the container and the water. The unit of measure for the mass of liquids is grams (g). Worksheet Measuring Mass Volume DEFINITION: Volume is how much space an object takes up. VOLUME OF A RECTANGULAR SOLID To calculate the volume of a rectangular prism, just measure the length, width, and height of the prism with a ruler, then multiply all three numbers. Use cm3 as your unit of measure. Volume = length x width x height 7 cm =8x5x7 = 280 cm3 5 cm 8 cm Volume VOLUME OF A LIQUID Measuring the volume of a liquid is easy. All you need to do is pour the liquid into a graduated cylinder. You will see that the water forms a curve called a meniscus. Read the number on the graduated cylinder that lines up with the bottom of the meniscus. That number is the volume of the liquid. The unit of measure for the volume of liquids is milliliters (ml). Volume To find the volume of a liquid, pour the liquid into a graduated cylinder and read under the meniscus. The volume in this graduated cylinder is 43 ml. Volume Click on the picture to practice reading different graduated cylinders. Make sure you have clicked the “PRACTICE” circle. Volume VOLUME OF AN IRREGULAR SOLID If your solid is an unusual shape, you need to Water Displacement Method use the water displacement method. First pour some water into a beaker or graduated cylinder and record how much water you have. Then place your object into the beaker or graduated cylinder. Record the volume of the water now. 4.8 ml 5.6 ml The last step is to subtract the two numbers. The amount the water went up is actually the volume of your object. Use cm3 as your unit of measure. volume = 5.6 - 4.8 = 0.8 cm3 Volume If your object floats, use the tip of a pencil to push it slightly under the water before reading the volume. Worksheet Calculating Volume