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The mass of magnesium used in this experiment is critical to determining the moles of hydrogen gas generated. The analytical balances used in Chemistry 1A labs are very sensitive to point that touching materials with your fingers before measuring them can affect the measurements. The balances are sensitive enough to detect dirt and oils from your fingers transferred to the magnesium. Would your experimental value of R increase or decrease if the mass of magnesium measured was artificially high due the touching it with your hands? Increase Decrease

The combustion of ammonia in the presence of excess oxygen yields NO2 and H2O: 4 NH3 (g) + 7 02 (g) → 4 NO2 (g) + 6 H2O (g) The combustion of 218 g of ammonia consumes g of oxygen. Atomic weights: N=14.01, H=1.01, O=15.99. Input values only with 2 decimal places.

Each point on the graph displays the amount of carbohydrates and calories found in ; cup of different vegetables. A line-of-best fit is also shown. 25 20 15 10 1 2 3 4 Carbohydrates (in grams) 5 Which linear equation best represents the line-of-best fit shown? O y = 3x – 4 O y= 4x + 3 O y 4r 6 O y = 5x +7 届 Calculator Calories

Acetic acid percentages in five vinegar samples were 4.98, 4.86, 4.97, 4.99. 5.08, 5.11, 4.97, 5.32 and 4.89. Could we reject any of these values ​​with 95% confidence? Q critical = experimental Q = Therefore (yes or no) the suspicious data can be rejected (write the value of the data that can be deleted, example 5.08).

Many common materials that we ingest, though quite safe in reasonable quantities, become toxic when taken in very large doses. A measure of toxicity is the LD 50 value (Lethal Dose, 50%). It is the quantity of material, expressed in mg of material per kg of subject-body-weight that, if administered to a population of subjects, would cause 50% of the population to die. The LD 50 value for FD&C Red Dye No. 40 is >10,000 mg/kg in rats. Assume that the LD 50 value for humans is the same as for rats. Calculate the number of number of glasses of Allura Red sports drink, each containing 8.8 mg of Allura Red, required to reach the LD 50 of 10,000 mg of Allura Red/kg body weight. Assume the person has a body weight of 165 lbs. 2.205 lbs 1 kg !! You may assume two significant figures but do not use sčientific notation. Do not include units with your answer. Your Answer: Answer

Many common materials that we ingest, though quite safe in reasonable quantities, become toxic when taken in very large doses. A measure of toxicity is the LD 50 value (Lethal Dose, 50%). It is the quantity of material, expressed in mg of material per kg of subject-body-weight that, if administered to a population of subjects, would cause 50% of the population to die. The LD 50 value for FD&C Red Dye No. 40 is >10,000 mg/kg in rats. Assume that the LD 50 value for humans is the same as for rats. Calculate the number of number of glasses of Allura Red sports drink, each containing 11.1 mg of Allura Red, required to reach the LD 50 of 10,000 mg of Allura Red/kg body weight. Assume the person has a body weight of 200 lbs. 2.205 lbs = 1 kg You may assume two significant figures but do not use scientific notation. Do not include units with your answer.

Many common materials that we ingest, though quite safe in reasonable quantities, become toxic when taken in very large doses. A measure of toxicity is the LD 50 value (Lethal Dose, 50%). It is the quantity of material, expressed in mg of material per kg of subject-body-weight that, if administered to a population of subjects, would cause 50% of the population to die. The LD 50 value for FD&C Red Dye No. 40 is >10,000 mg/kg in rats. Assume that the LD 50 value for humans is the same as for rats. Calculate the number of number of glasses of Allura Red sports drink, each containing 9.3 mg of Allura Red, required to reach the LD 50 of 10,000 mg of Allura Red/kg body weight. Assume the person has a body weight of 225 Ibs. 2.205 Ibs = 1 kg %3!

(Incorrect) An impure sample of hydrocarbon having a total mass of 41.0 g undergoes combustion analysis to generate 82.6 g CO₂(g) and 16.9 g H₂O(g). Assuming that the impurities do not contain carbon or hydrogen, what percentage of the initial sample is the pure hydrocarbon? Provide the numerical value of your response in decimal notation rounded to 3 significant figures. You answered: 4.58 The correct answer is: 59.5%

Compare: capacity factor, k' I 0.18 0.16 0.14 0.12 0.1 II 0.08 0.06 0.04 0.02 0 O the quantity in I is greater the quantity in II is greater the two quantities are equal O the relationship cannot be determined due to insufficient information

JOP3JH-1J n/WsvrRAXK6XnHkiRvH2t180AR2-EPP O CHEMICAL REACTIONS Solving for a reactant using a chemical equation Ammonia (NH,) chemically reacts with oxygen gas (0,) to produce nitric oxide (NO) and water (H,0). What mass of water is produced by the reaction of 9.8 g of oxygen gas? Round your answer to 2 significant digits. x10 Explanation Check 2020 McC DELL -> %23 $ & 4 8.

The actual mass of a 144 Sm atom is 143.911995 amu. (Consult Appendix B for any needed reference values. Enter unrounded values for your answers.) (a) Calculate the mass defect in amu/atom and in g/mol for this isotope. amu/atom g/mol (b) What is the nuclear binding energy in kJ/mol for this isotope? kJ/mol

when drawing melting point composition diagram for a mixture of something such as cinnamic acid and urea comparing melting point vs composition for organic chemistry, if i have three different compositions (1:4, 4:1,1:1) should i have 3 different graphs or would this all be on the same graph? and how do i convert grams to moles for example for composition 1:4 my data was 0.8003 g : 3.1917 g?

Analytical chemist from Petroleum Development Oman extracted petroleum from crude oil and measured the quantity lost by the extraction to tell how much of the petroleum was. Quantity of Petroleum lost (%):10.8, 11.6, 9.4, 7.8, 9.2, 9.5, 10.6, 11.6Should the value 7.8 be rejected from the set of the above results.

Asking for Q 9

On 12 and 13 I got a negative scientific on one and a positive on the other. Did I make a mistake typing it into my calculator?

For the following problem you should describe in complete sentences the steps you would take to solve the problem and indicate what information you obtain in each step. You do not need to find a numerical answer. You might want to use dimensional analysis to show that your answer has the correct units. Each year in the spring rhododendrons should be fertilized. The recommended fertilizer is described as 10-8-6, which means 10% N, 8% P2O5 and 6% K2O by mass. How many grams of ammonium nitrate (NH4NO3) would you need to produce 1 kg of fertilizer that is 10% N? You do not need to consider the other compounds that are necessary to provide phosphorous and potassium.

the Daily Value for saturated fat is 20 grams (g), which equals 100% DV. If the Nutrition Facts Label says one serving of a food contains 1.5 g of saturated fat, how much % DV this meals contains from the maximum amount of fat that is recommended for you per day.

Many common materials that we ingest, though quite safe in reasonable quantities, become toxic when taken in very large doses. A measure of toxicity is the LD50 value (Lethal Dose, 50%). It is the quantity of material, expressed in mg of material per kg of subject-body-weight that, if administered to a population of subjects, would cause 50% of the population to die. The LD50 value for FD&C Red Dye No. 40 is >10,000 mg/kg in rats. Assume that the LD50 value for humans is the same as for rats. Calculate the number of mg of Allura Red present in an 9 fluid ounce glass of the beverage you used in this lab and use this calculation to determine the number of such glasses of Allura Red sports drink required to reach the LD50 of 10,000 mg of Allura Red/kg body weight. Assume that the concentration of Allura Red in the beverage is 0.000038 M and the person has a body weight of 175 lbs. The molar mass of Allura Red is 496.42 grams/mol 1 fl oz = 29.5735 mL 2.205 lbs = 1 kg You may assume…

Many common materials that we ingest, though quite safe in reasonable quantities, become toxic when taken in very large doses. A measure of toxicity is the LD50 value (Lethal Dose, 50%). It is the quantity of material, expressed in mg of material per kg of subject-body-weight that, if administered to a population of subjects, would cause 50% of the population to die. The LD50 value for FD&C Red Dye No. 40 is >10,000 mg/kg in rats. Assume that the LD50 value for humans is the same as for rats. Calculate the number of mg of Allura Red present in an 9 fluid ounce glass of the beverage you used in this lab and use this calculation to determine the number of such glasses of Allura Red sports drink required to reach the LD50 of 10,000 mg of Allura Red/kg body weight. Assume that the concentration of Allura Red in the beverage is 0.000038 M and the person has a body weight of 175 lbs. The molar mass of Allura Red is 496.42 grams/mol 1 fl oz = 29.5735 mL 2.205 lbs = 1 kg You may assume…

In replicate analyses, the carbohydrate content of a glycoprotein ( a protein with sugars attached to it) is found to be 12.6, 11.9, 13.0, 12.7, and 12.5 g of carbohydrate per 100 g of protein. (a) Find the mean of the measurements.

a Assume that mitochondria are cylinders 8.00 um in length and 0.800 pm in diameter. What is the volume of a single mitochondrion? The volume of a cylinder is given by the expression: V = n x y2 x h Volume= m

1a. Throughout the experiment, what are some possible sources of error that could have led to someone recovering a significantly smaller amount of table salt (NaCI) than was originally present in the sample mixture. 16. What are some possible sources of error that could have led to someone to appear to have recovered a significantly larger amount of sand (SiO2) than was originally present in the sample mixture.

100- 8 8 Relative Intensity $ 20- 0- Relative Intensity 10 200- 80- 40- 20- 0- 10 20 30 m/z 20 20 100 $10 Chlorine OR Bromine OR Neither Chlorine OR Bromine OR Neither 90 100 100- Relative Intensity DO- ģ 20- 0 100 80 10 8 Relative Intensity 3 0- 10 40 30 60 15 m/z Chlorine OR Bromine OR Neither 35 40 45 m/z weytekakumpumakija 30 100 110 55 Chlorine OR Bromine OR Neither

II. BOILING POINT ELEVATION: The temperature of a boiling 50 mL of distilled water in an Erlenmeyer flask with a small flame was taken to be 98°C. The bulb of the thermometer must not touch the bottom or sides of the Erlenmeyer flask. In another Erlenmeyer flask, 2.83 grams of urea is dissolved in 10 grams of distilled water. The solution was let to boil gently and its boiling point was recorded to be 101°C. DATA AND RESULTS: (Show all pertinent computations on the space provided if applicable. Answers with no computation will not be considered.) Mass of urea in grams Mass of water in grams Boiling point of distilled water in degrees Celsius Boiling point of urea solution in degrees Celsius Molecular weight of urea in g/mol (experimental) Molecular weight of urea in g/mol (calculated) Percent Error of Molecular weights of urea Change in boiling point SOLUTION/S: