Ch's 1, 2 & 3 Flashcards
64,000
.021
- 4 x 10^4
2. 1 x x 10^-2
Density =
mass/volume (typically g/cm^3 or g/mL
specific gravity =
density of sample / density of water (UNITLESS!!!!)
Tf =
Tf = 1.8 (Tc) + 32
K =
Tc + 273
1 K =
1 C
Boiling point of water in F, C, and K
212F, 100C, 373K
Normal body temp in F, C, and K
98.6F, 37C, 310K
Freezing point of water in F, C, and K
32F, 0C, 273K
energy of motion (examples)
kinetic energy
swimming, water flowing over dam, working out
_____ is energy stored for use at a later time. It
is determined by the position of an object or the
chemical composition of a substance. Examples?
Potential energy
are the following:
• water at the top of a dam
• a compressed spring
• chemical bonds in gasoline, coal, or food
____ is the energy associated with the movement of particles.
The ___ the particles move, the greater the heat or thermal energy of the substance.
Given an ice cube, as heat is added, the H2O molecules
• that are moving slowly increase their motion.
• eventually have enough energy to change the ice cube from a solid to a liquid.
Heat
faster
The ____ is defined as the amount of energy needed to raise the temperature of 1 g of water by 1 °C.
calorie
Nutritionists burn food in a ____ that
- is used to measure heat transfer.
- consists of a steel container filled with oxygen and a measured amount of water.
- indicates the heat gained by water, which is the heat lost by a sample during combustion.
In a calorimeter, the burning of a food sample increases the temperature of the water, which is used to calculate the energy value of the food.
calorimeter
_____ from burning a food sample in a calorimeter is used to determine the energy value for the food.
Heat released
1 Cal =
1000 calories
A measure of toxicity which is the concentration of the substance that causes death in 50% of the test animals
LD50
dosage is typically measure in:
mg/kg
mcg/kg
LD50 of caffeine is 192mg/kg (slow down Calvin)
density =
mass of a substance / volume of a substance
specific gravity =
density of sample / density of water
specific gravity
relationship of a substance and the density of water
is calculated by dividing the density of a sample by the density of water, which is 1.00 g/ mL at 4 deg C
UNITLESS!
Normal range of temperatures for human:
100.4 to 96.8 (average of 98.6)
hypothermia in human
95
hyperthermia in human
105.8 (death possibly impending)
On Celsius scale there are ___ degrees between boiling and freezing points
100
On Fahreneit scale there are ____ degrees between boiling and freezing points
180
Scientists have learned that the coldest temperature possible is:
-273 deg C
0K
absolute zero
0 K (-273 deg C)
freezing point of water
32 deg F
0 deg C
273 deg K
normal body temp
98.6 deg F
37 deg C
310 K
boiling point of water
212 deg F
100 deg C
373 K
the number obtained by counting
exact number
a part of the name of a metric unit that precedes the base unit and specifies the size of the measurement
prefix
a ratio in which the numerator and denominator are quantities from an equality
conversion factor
the relationship between two units that measure the same quantity
equality
the digits recorded in a measurement
significant figures (degree of accuracy)
the number obtained when a quantity is determined by using a measure device
measured number
the relationship of the mass of an object specified to its volume expressed as grams per cubic centimeter or grams per milliliter
density
the relationship between the density of a substance and the density of water
specific gravity
the ability to do work
energy
the SI unit of energy
Joule
the energy of motion
kinetic energy
the amount of heat that raises the temp of exactly 1 gram of water exactly 1 deg Celsius
calorie
a change in physical properties of a substance with no change in its identity
physical change
a type of energy that is stored for future use
potential energy
1000 cal
kilocalorie
raise 1 gram of water by 1 deg celsius
calorie
the nutritional calorie
Cal
Cal =
1 kcal, or 1000 calories
the energy content of a food is the sum of kilocalories or kilojoules from….
carbs, fat, protein
when a substance is burned in a calorimeter, the water that surrounds the reaction chamber absorbs the heat given off. What is calculated?
The heat absorbed by the water is calculated, and the energy content for the substance (energy per gram) is determined
