A few days ago
trishtar

# help!…unit conversion problems?

1. A candy recipe calls for sugar mixture to be brought into “softball stage” (234-240 degrees C). A student borrows a thermometer of range -10 to 110 degree C from the lab to do the assignment. Will the thermometer serve it’s purpose?

2. An empty container weighs 65.4 g. When an unknown liquid was added, it weighs 84.6 g and reads 90 ml. What is its density in kg/cm3?

A few days ago
jiffyville

the first question is incorrectly phrased. softball stage is between 234-240 degrees F, so you need to see if that range is less than 110 degrees C.

converting degrees F to degrees C:

if you don’t know this i will explain. the range of the liquid phase of water is between 0 C and 100 C, and 32 F and 212 F, so the celsius range is 100 and the fahrenheit range is 180. the ratio is 5:9. so, C = 5/9 * (F – 32)

and F = 9/5 * C + 32

so, 110 C is 9/5 * 110 + 32 = 198 + 32 = 230

the answer is no because the thermometer will only read up to 230 F, and the “softball stage” is between 234 and 240 F

second question. the mass of the liquid divided by the volume of the liquid will give us the density.

the mass of the liquid is the difference between the mass after it was added and the empty container’s mass. 84.6 – 65.4 = 19.2 g

19.2/90 = .21333 g/ml

milliliters are equal to cubic centimeters, so we don’t need to worry about the denominator, but the numerator says it is supposed to be in kilograms, so we will need to divide the answer by 1000 because a kilogram is 1000 grams.

so, the answer is .00021333 kg/cm³.

😉

0

A few days ago
Rowin
1. No. It is not possible because the limit of the thermometer is only up to 110 deg C. You cant use to read temp beyond 110 deg C.

2. the answer is 0.00021333333333 kg/cm3.

A. subtract the weight of the container w/ liquid from the weight of the container.

B. So the liquid is 19.2g per 90ml, divide the #s.

C. the result divide it by 1000. the solution is in http://i169.photobucket.com/albums/u219/rowin_bigman/solution.jpg

0