A 5.00 milliliter sample of a substance has a mass of 12.5 grams. What is the mass of a 100 milliliter sample of the same substance?
Question 5 options: 40.0 g 125 g 400 g 250 g
A 5.00 milliliter sample of a substance has a mass of 12.5 grams. What is the...
A scientist begins with 250 grams of a radioactive substance. After 250 minutes, the sample has decayed to 36 grams. Write an exponential equation f(t) representing this situation. (Let f be the amount of radioactive substance in grams and t be the time in minutes.) f(t) 250e 0.0087t x To the nearest minute, what is the half-life of this substance? 89 min Use the model for continuous exponential decay, y = Ao e-kt, where y is the amount of radioactive...
A mole of a substance has the same mass in grams as one unit (atom or molecules) has in atomic mass units. True False
17. One milliliter of plasma is diluted 1/10 in tube 1. Then 1 mL of the dilution in tube 1 is added to 4 mL in a second tube. One milliliter from tube 2 is then added to 9 mL diluent in tube 3. What is the substance (plasma) volume in the third tube? 18. What is the specific gravity of a substance if 5 mL of the substance weighs 6.5 g, but the substance is only 50% pure? 19.What...
Qustion Campleon Status: QUESTION 7 What is the mass of a 4.110-mol sample of sodium hydroxide? Oa. 98.6 g Ob0.1028 g Oc 164,4 g O d.9.732 g Oe. 40.00 g QUESTION 8 A sample of ammonia has a mass of 89.9 g. How many molecules are in this sample? Oa541 x 1025 molecules Ob.5.28 molecules Oc3.18x 1024 molecules Od 1.14 x 1023 molecules x 10-15, molecules QUESTION 9 A mole of a chemical substance represents Oa.6.02 x 1025 chemical particles...
A molecule of an unknown substance has a mass of 1.75⋅10−211.75⋅10-21 grams. What is this substance's molar mass?
A) You are using a Geiger counter to measure the activity of a radioactive substance over the course of several minutes. If the reading of 400. counts has diminished to 100. counts after 48.2 minutes , what is the half-life of this substance? B) An unknown radioactive substance has a half-life of 3.20 hours . If 24.3 g of the substance is currently present, what mass A0 was present 8.00 hours ago? C) Americium-241 is used in some smoke detectors....
A 12.5.% sucrose solution by mass has a density of 1.05 g/cm3. What mass of sucrose is present in a 45.0-mL sample of this solution?
A sample of 12 grams of a substance that does not dissociate is dissolved in 80 g of water. The solution freezes at -1.94 ° C. What is the molecular weight of the substance if the cryoscopic constant for water is 1.86 ° C / m?
What is the mass (in grams) of a femur (leg bone) having a volume of 118 cc? The density of bone is 1.8 g/cc. Iron has a density of 7.8 g/cc. What is the mass, in grams, of a 4.4 cm3 piece? What is the volume (in cc) of a sample of mercury that has a mass of 20.5 g. The density of mercury is 13.6 g/cc. Aspirin has a density of 1.40 g/cc. What is the volume in cubic...
erksheet 7-Rey 10 A 10.0 mL sample of sodium chioride solution that has a mass of 16.78 g is placed in an Solutions evaporating dish and evaporated to dryness. The residue has a mass of 6.55 g. Calculate the following concentrations for the NaCl solution mass/mass (m/m) percent mass/volume (m/v) percent malarity A 4.00 % (g/mL) KI solution has a volume of 65.0 mL. How many grams of KI are in the sample? How many grams of a 35% (...