A. In the experiment, The molar volume of a gas. Mg (s) + 2HCl (aq) = MgCl₂​ (aq) + H₂ ​(g), the magnesium ribbon was dissolved in hydrochloric acid, a monoprotic acid, to produce H₂ ​gas. If phosphoric acic, a triprotic acid, were used to react with the magnesium rather than hydrochloric acid, does that affect the amount of H₂​ gas produced?. Write balanced equations for the reaction og Mg with 1) HCl and 2) phosphoric acid to help explain your answer.

B. In this experiment, Mg (s) + 2HCl (aq) = MgCl₂​ (aq) + H₂ ​(g), ​you injected 5 ml of HCl into the flask and immediately pulled back the plunger to its original position. Explain (a) why this latter action was done and (b) if the plunger weren't pulled back to its original position, how would this affect the subsequent molar volume calculation (say, under STP condictions). Answer this question by stating the molar volume calculation would be higher, lower, or not affected, and proide a plausible explanation for your choice.

In a controlled experiment, it takes 3700 J to melt the amount of metal that is in a weld bead with a cross-sectional area of 6.0 mm2 that is 150.0 mm long. (a) Using Table 28.2, what is the most likely metal? (b) If the heat transfer factor is 0.85 and the melting factor is 0.55 for a welding process, how much heat must be generated at the welding source to accomplish the weld?

An article in Journal of Structural Engineering presents the results of an experiment that evaluated a standard method for estimating the brace force for a truss. In a sample of 360 short test trusses the method underestimated the force for 45 of them, and in a sample of 400 long test trusses, the method underestimated the force for 60 of them. Find a 95% confidence interval for the difference between the underestimation rates for long and short trusses.

An experiment was conducted to test the effect of a new drug on a viral infection. After the infection was induced in 100 mice, the mice were randomly split into two groups of 50. The first group, the control group, received no treatment for the infection, and the second group received the drug. After a 30-day period, the proportions of survivors, p?₁ and p?₂, in the two groups were found to be 0.32 and 0.60, respectively.

(a) Is there sufficient evidence to indicate that the drug is effective in treating the viral infection? Use ? = 0.05.

State the null and alternative hypotheses.

H₀: (p₁ ? p₂) ? 0 versus H_a: (p₁ ? p₂) = 0H₀: (p₁ ? p₂) = 0 versus H_a: (p₁ ? p₂) ? 0    H₀: (p₁ ? p₂) = 0 versus H_a: (p₁ ? p₂) > 0H₀: (p₁ ? p₂) = 0 versus H_a: (p₁ ? p₂) < 0H₀: (p₁ ? p₂) < 0 versus H_a: (p₁ ? p₂) > 0

Find the test statistic and rejection region. (Round your answers to two decimal places. If the test is one-tailed, enter NONE for the unused region.)

State your conclusion.

H₀ is rejected. There is sufficient evidence to indicate that the drug is effective in treating the viral infection.H₀ is not rejected. There is insufficient evidence to indicate that the drug is effective in treating the viral infection.    H₀ is not rejected. There is sufficient evidence to indicate that the drug is effective in treating the viral infection.H₀ is rejected. There is insufficient evidence to indicate that the drug is effective in treating the viral infection.

(b) Use a 95% confidence interval to estimate the actual difference (p₁ ? p₂) in the survival rates for the treated versus the control groups. (Round your answers to two decimal places.)
to

2. An experiment is to be conducted using a crossover design. The statistician informs the investigator that a rest period, or washout period, should be included in the study plan. The purpose of the rest period is to eliminate or reduce (1 mark)

1. Observer data
2. Missing data
3. Residual treatment effects
4. Problems with patient compliance
5. Adverse drug experiences

An experiment was conducted to test the effect of a new drug on a viral infection. After the infection was induced in 100 mice, the mice were randomly split into two groups of 50. The first group, the control group, received no treatment for the infection, and the second group received the drug. After a 30-day period, the proportions of survivors, p?1 and p?2, in the two groups were found to be 0.36 and 0.64, respectively.

(a) Is there sufficient evidence to indicate that the drug is effective in treating the viral infection? Use ? = 0.05.

State the null and alternative hypotheses.

H0: (p1 ? p2) < 0 versus Ha: (p1 ? p2) > 0

H0: (p1 ? p2) = 0 versus Ha: (p1 ? p2) < 0

H0: (p1 ? p2) ? 0 versus Ha: (p1 ? p2) = 0

H0: (p1 ? p2) = 0 versus Ha: (p1 ? p2) ? 0

H0: (p1 ? p2) = 0 versus Ha: (p1 ? p2) > 0

Find the test statistic and rejection region. (Round your answers to two decimal places. If the test is one-tailed, enter NONE for the unused region.)

test statistic: z =

rejection region: z >, z <

State your conclusion.

H0 is not rejected. There is insufficient evidence to indicate that the drug is effective in treating the viral infection.

H0 is rejected. There is sufficient evidence to indicate that the drug is effective in treating the viral infection.

H0 is not rejected. There is sufficient evidence to indicate that the drug is effective in treating the viral infection.

H0 is rejected. There is insufficient evidence to indicate that the drug is effective in treating the viral infection.

(b) Use a 95% confidence interval to estimate the actual difference (p1 ? p2) in the survival rates for the treated versus the control groups. (Round your answers to two decimal places.)

_____ to _____

You may need to use the appropriate appendix table or technology to answer this question.

Density of plastic

Your challenge in this experiment is to determine the density of a mystery plastic, using two different step-by-step procedures. For sufficient error analysis, each method should be completed at least twice (e.g., Method A: Trial #1 & Trial #2; Method B: Trial #1 & Trial #2).
The plastic is in the form of small (~1 cm), irregularly shaped pieces. You will have access to several pieces of the plastic. The irregular shapes mean that it will not be possible to calculate the volume of the pieces by measuring their dimensions. In addition to the normal chemistry laboratory equipment and water, there will be methanol and ethylene glycol available in the lab this week.

My question is

Write two detailed, step-by-step procedures that use different ways to determine the density of the plastic.

In a hurry to complete the experiment, Joseph failed to calibrate the spectrophotometer. As a result, all absorbance values for the standard solutions that are measured and recorded are too high. How will this affect the following for the Test Solutions in Parts B and C? a: will the equilibrium concentrations of FeNCS2+ be too high, too low, or unaffected? Explain b: Will the equilibrium concentrations of Fe3+ be too high, too low, or unaffected? Explain. c: Will the calculated equilibrium constants be too high, too low, or unaffected? Explain

An Excel ANOVA table that summarizes the results of an experiment to assess the effects of ambient noise level and plant location on worker productivity.

1. State the 2 null hypothesis for the F statistics listed above
2. At the 1% significance level, do you reject or fail to reject your null hypothesis?
3. At the 15% significance level, do you reject or fail to reject your null hypothesis?

An experiment was conducted to test the effect of a new drug on a viral infection. After the infection was induced in 100 mice, the mice were randomly split into two groups of 50. The first group, the control group, received no treatment for the infection, and the second group received the drug. After a 30-day period, the proportions of survivors, p̂₁ and p̂₂, in the two groups were found to be 0.38 and 0.62, respectively.

(a) Find the test statistic and rejection region. (Round your answers to two decimal places. If the test is one-tailed, enter NONE for the unused region.)

(b) Use a 95% confidence interval to estimate the actual difference (p₁ − p₂) in the survival rates for the treated versus the control groups. (Round your answers to two decimal places.)