The half-life of caffeine is 5.5 hours. You drink a double espresso, which contains 128 mg of caffeine. You cannot sleep with more than 20 mg of caffeine in your system. So how long are you going to be awake?

Q: a breakfast of ceriel, orange juice, and milk contain 230 nutritional calories. Exress this energy…

A: GivenEnergy  = 230 Calories

Q: How many electrons have been removed or protons added?

A:

Q: what is the healthiest thing to drink

A: It has been known recently that one of the healthiest thing to drink is green tea.

Q: What is the cost per mile to drive a van that has a gas mileage of 12.7 miles per gallon and the…

A: From the question it is given that Distance covered = 1 mileMileage of van = 12.7 miles per…

Q: You have one kilogram of feathers and one kilogram of lead. Which has the smallest density?

A: Answer Feathers

Q: The mass of a liter of milk is 1.032 kg. The butterfat that it contains has a density of 865 kg/m3…

A:

Q: A typical timber wolf has a mass of 40 kg, a typical jackrabbit a mass of 2.5 kg. Given the scaling…

A:

Q: The density of iron is 8 grams per cubic centimeter. The atomic mass of iron is 56 grams per mole…

A:

Q: Assuming that there are 5 × 1013 cells in the humanbody and that ATP is turning over at a rate of…

A: The watts consumed by human body can be given by Watts consumed=ATP molecules turnover/sec×number of…

Q: A colony of bacteria originally contains 700 bacteria. It doubles in size every 40 minutes. How many…

A: Given : Original Population of bacteria=700 Time taken to double up once=40 minutes We have to find…

Q: A person contains 7 L of blood. Blood is composed of 55 percent plasma and 45 percent blood cells by…

A: (a) It is given that blood is composed of 55% of plasma by volume. The volume of plasma in 7L of…

Q: The diameter of a water droplet is 8um. This value in the S.I. system of units is a. 8x10-3 m O b.…

A:

Q: 4. Cobalt-60 has a half-life of approximately 5 years. If 53 g of the material was stored for 20…

A:

Q: How many protons, neutrons, and electrons are in a neutral atom of carbon-14?

A: Atomic number is given by number of protons present in an atom. Z = number of protons Mass number is…

Q: After an injection of Drug Y, the concentration of the drug in the bloodstream drops at the contin…

A:

Q: what coefficient is placed in front of H2O to balance this equation? 2A(OH)3 + 3H2SO4 --> AI2(SO4)3…

A: Given that 2Al(OH)3 + 2H2SO4 ------> Al2(SO4)3 + ______H2O

Q: The average US home uses 50,000,000 Joules of electrical energy per day. How many Joules will…

A:

Q: How many moles of iron is in a 1kg sample of iron?

A: To determine No of moles in 1 kg sample of iron

Q: The volume of a sample of oxygen gas changed from 10 mL to 11 mL as the temperature changed. Is this…

A: Solution: Givwn that The volume of a sample of oxygen gas changed from 10 mL to 11 mL as the…

Q: A 75 kg sprinter accelerates from 0 to 8.0 m/s in 5.0 s. What is the output erergy, in kJ…

A: Data provided:  Mass (m) = 75 kg Initial velocity (v0) = 0 m/s Final velocity (vf) = 8.0 m/s Time…

Q: How many individual atoms are in a water molecule?

A: The molecular formula for water is

Q: If the fuel efficiency of an automobile is 27 miles per gallon, what is its fuel efficiency in…

A:

Q: If you dispense 0.3 grams of aspirin, how many milligrams are you giving?

A: CONCEPT: Method of conversion of unit is used to find required value. 1 g=1000 mg where g is gram…

Q: A study finds that the metabolic rate of mammals is proportional to m314, where m is the total body…

A:

Q: If a 3.5-ounce portion of spinach costs $0.25, how much would a 5-lb box cost?

A: Given: The cost of 3.5 ounce spinach is 0.25$. Mass of the box is 5 lb. Concept: There are 16 ounces…

Q: A 46.60-gram pycnometer was filled with 100.50 grams of liquid. When filled with insoluble powder,…

A: Mass of pyncrometer, mp=46.60 gMass of liquid, ml=100.50 gMass of insoluble powder+pyncrometer,…

Q: How many molecules of carbon dioxide are there in 44g of carbon dioxide?

A: Number of molecules

Q: A study finds that the metabolic rate of mammals is proportional to m3/4, where m is the total body…

A:

Q: An adult inhales about 6.0××10−4−4 m3m3 of fresh air during a breath. Only 20%% of fresh air is…

A: Let P be the pressure in the lungs, V be the volume of the fresh air, n be the number of moles of…

Q: A balloon with a volume of 2.0 L is filled with a gas at 3 atmospheres. If the pressure is reduced…

A: "Since you have asked multiple question, we will solve the first question for you. If you want any…

Q: A sample of gas has a volume of 12 L and a pressure of 200 kPa. If the pressure of gas is increased…

A:

Q: An average person normally excretes 1,375ml of urine each day. If the density of urine is 1.025g/ml,…

A: V = 1375 ml = 1375 x 10-3 L ρ = 1.025 g/ml = 1.025 kg/L M = ?

Q: The population of bacteria in cultures grows at a rate proportional to the number of bacteria…

A: The growth rate of the population of bacteria is, Here, N denotes the number of bacteria and k…

Q: A diet decreases a person's mass by 4 % . Exercise creates muscle and reduces fat, thus increasing…

A:

Q: You take 1000 mg of a vitamin and your friend takes 1 g of the same vitamin. Who takes more…

A:

Q: The common Eastern mole, a mammal, typically has a mass of 75 g, which corresponds to about 7.5…

A:

Q: The density of an object whose mass is 50 g and occupies a volume of 50 cubic centimeter is equal to

A: Given in question : Mass of object(m) = 50 g                                  Volume of an object(V)…

Q: If 10 kg of rock salt is placed in water, it dissolves at a rate proportional to theamount of salt…

A: Let the x be the amount of dissolved salt in the water. The undissolved amount of salt can be…

Q: SA person tries a new diet where they eat onlLy eggs as their protein source. .They lost 1.7 ke in a…

A: Given Weight lost in one week = 1.7 kg Average rate of weight loss R = 1.7 kg / week 1 kg = 1000 g 1…

Q: In a standard gas grill propane tank, there is approximately 4,579 mL of propane (C3H8). At a…

A: Given,V1=4579mLP1=1798kPaT1=550C=55+273KT1=328KandP2=1025 kPaT2=250C=298K

Q: The FDA recommends that adults consume 9 x 10 -4 grams of copper per day to help with enzymes that…

A: Given, the FDA recommends that adults consume w = 9 x 10-4 gm of copper per day to help with enzymes…

Half Life

The concept of Half Life has numerous practical applications some of them includes figuring out the effective drug dosage to finding out when a radioactive becomes safe to use. If you look for a career in Nuclear Physics you will need this concept.