Week 1 Lab - Introduction to Science Question Set

The diagram shows the setup of an experiment. A few observations of the experiment are listed in the table below the diagram. Experimental Observations Observation Description 1 Color of solution turned blue 2 Shiny hair like crystals deposited on the copper strip Which of the following is the correct explanation for one of the given observations?  Observation 1 is a result of silver ions moving into the solution.  Observation 2 is a result of nitrate ions moving into the solution.  Observation 1 is a result of silver ions changing their oxidation state.  or Observation 2 is a result of silver ions changing their oxidation state.

Can you please help with question 5?      Add one teaspoon of boiling water to an effervescent aspirin tablet. Stir with a teaspoon. If it doesn’t dissolve completely, add another half teaspoon of boiling waterand repeat until the tablet has fully dissolved. ( will probably require less than 15 ml for a 300 mg tablet) When it appears that most of the tablet has dissolved, butthere are some solid particles, heat the mug in a microwave for 10 second increments until the water came to the boil (approx. 3x) and all of the solid particlesdissolved. Leave the solution to cool to room temperature and then place in a fridge and observe if crystals form.• Questions to ask:1. What might the fizzing bubbles be?2. Can you give a chemical explanation?3. Can you write a chemical reaction equation with aspirin reacting with something to give a gas and aspirin in another form?4. What might be the formulation (what the manufacturer mixes with aspirin in making the tablet) “trick” for aspirin to improve…

Can you please answer these and give me an explanation.

1. (answer the questions in the tan boxes in the tables below each question) A student conducted an investigation to determine the effect of water temperature on the amount of sugar that dissolves in a beaker of water. Identify components for trial 1 of this investigation. Beaker Number 1 2 3 4 Amount of Water (mL) 100 100 100 100 Amount of Water (mL) Trial 1 Temperature of Temperature of Amount of Sugar Sugar (°C) Water (°C) Dissolved (g) 20 20 20 20 Temperature of Sugar 5 10 15 20 185 189 194 204 Temperature of Water Terms Variable Constant Amount of Sugar Dissolved

Ms. Tan came to the laboratory for blood tests because her physician suspected renal disease. The tests ordered were serum BUN, creatinine, and electrolytes. The blood specimen was obtained and processed. When the laboratory scientist received the serum to perform the tests, he noticed that the serum had a reddish tinge. What factor/s could cause this to happen to a serum specimen?     2. Is the sample acceptable for use? Elaborate your answer   3. What are the advantages of using plasma compared to serum in chemical analyses?

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Exactly 15.0g of a substance can be dissolved in 150.0g of water. What is the solubility of the substance in grams per 100g of water?

2. In case of an accident in the classroom, who should be notified immediately? 3. Why is it a safety procedure to tie back long hair in the laboratory? 4. Why should a student not eat or drink in the laboratory? 5. Why should any spills be reported and cleaned immediately? 6. Why should you wash your hands after every laboratory period? 7. Why is rough play in the laboratory dangerous? 8. When would the wearing of safety goggles be a proper procedure? 7

Suppose your instructor places a can of regular and diet cola in a large container filled with water. What might you expect happen based on the results of this experiment?

Chemistry Five modern United States pennies are measured three times each on a balance, and their measured masses are compared to the actual mass of a penny (2.5000 grams according to US Mint).   a. When looking at the precision of the balance, which would be more ideal: one relative standard deviation value for fifteen measurements or five relative standard deviation values for the five pennies?   2. What is the relationship between solubility and density? Why is it important to consider the solubility of substances when determining their densities?   3. Why is it ideal to use only 10 mL or greater of a liquid when calculating for density?   4. Assume you have stacked 5 liquids on top of one another in a column. Each liquid (3 mL) has varying densities. What will happen to the densities of the liquids if the volume of each increased?   5. What does percent error indicate: quality of instrument (refer to the balance and penny example in Problem #1) or quality of penny? Why?

1. Seawater is composed of salt, sand, and water. Is seawater a heterogenous mixture or homogenous mixture? 2. Suppose there are four unknowns in bottles: three of the bottles are solutions and one is a pure substance. How are you going to determine which of the unknown is a pure substance?

a. Convert 15 ppb to units of percent by mass (density is 1.00 g/mL) b. Protective layer can form from the precipitation reaction of lead(II) with carbonate to form lead(II) carbonate.  Write a balanced chemical equation for this reaction Please show work when solving the questions. Thanks!

Need all three plz

A 1185 mL sample of drinking water was found to contain 20.5 mg of lead. Calculate the concentration of lead in milligrams per liter. concentration: mg/L MacBook Air トト F11 F12 888 FB F7 F3 F4 24 & * 4 5 6 7 8 Y K

Starting with question 2 up to question 4

MODIFIED TRUE OR FALSE Explain each underlined word why is true or false

This isn't a graded question... please don't reject it and solve this on your own Any help would be appreciated please

6. Suppose you start with 100 mL of a 5% (5g/dL) sucrose solution and dilute it by adding 300 mL of distilled H20. a) What is the total volume of the new solution in mL? b) What is the sucrose concentration of the new solution in mg/dL? c) How many grams of sucrose are contained in the total volume of this solution?

A laboratory technician needs 1.00 L of 0.125 mol/L sulfuric acid solution for a quantitative analysis experiment. A commercial stock of 5.00 mol/L sulfuric acid solution is available from a chemical supply company. How much sulfuric acid should the lab technician take from the stocK

Epsom salt is a product that may be added to a bath to help ease sore muscles. Epsom salt crystals Epsom salt ground crystals A materials scientist tested two forms of Epsom salt under different conditions to see which would dissolve the fastest. The test information is displayed in this table. Sample Mass Form Water temperature A 50 grams ground crystals 30°C B 100 grams crystals 20°C 50 grams 100 grams ground crystals 20°C crystals 30°C Which sample of Epsom salt would you expect to dissolve the fastest? O A. A В. В ос. С O D. D

Question 3 This question concerns states of matter. a. Describe the arrangement and movement of particles in each of the three states of matter. Use diagrams to help you with your explanation. Explain what happens to the particles in a liquid during boiling. separate the dyes in a sample of food colouring. Explain how this method works using appropriate diagrams. road surfaces. Explain why this is done and what effect it has. b. Food colourings contain a mixture of water-soluble dyes. Devise a method to c. When there is a lot of ice in the roads in the UK, tonnes of salt are added to the

To make 5.00 L of a fruit punch that contains 10.0% v/v ethanol, how much 95.0% v/v ethanol must bemixed with how much fruit juice?a. 1.90 Lb. 48.0 mLc. 526 mLd. 190 mL

Golf balls are made up of rubber.What the properties of rubber to work properly.write an essay on its properties of 300 words and also give the source and reference from where you have collected the data.