Question

Solid Investigation Question:

What is the identity of an unknown solid piece of metal?

Specific questions:

1. What are the observable physical properties of your sample?

2. If provided with a table of densities of metals, how might you use this information to identify your piece of metal?

a. Given that calculating a physical constant is more reliable using a graph with multiple measurements from multiple samples than using measurements from a single sample, how could you use a graph to determine density if you are provided metal pieces of various lengths. Please note that you are required to submit a graph for your micro-project. Your graph will need to have a title, axes labels and a trendline as well as trendline equation. i

. How would you determine volume?

ii. What would you plot in order to get a slope that gives you density?

iii. What is the density of your sample?

Solution Investigation Question:

What are some of the key characteristics of unknown sample of an aqueous solution containing an ionic compound?

Specific questions: 1. Given that the cation is from Group 1A, what is the identity of the group 1A metal ion in your solution?

2. Given that the ionic compound contains either chloride or hydroxide, how can you determine which? (Two pieces of evidence are required and one must be related to solubility rules)

3. What is the concentration of your solution? (Your unknown sample is known to be about 1 M, but you need to determine the concentration to 3 significant figures using titration. You should plan ahead so that you know approximately what volume of your sample you will need in order to use approximately 25 mL of 0.100 M sulfuric acid for the titration). I'm not sure how to answer either of these problems

Answer 1

identity of an unknown solid piece of metal -its density -for eg density of copper=10.49 g/cm3

Specific questions:

1. The observable physical properties of sample metal are =its color,lustre,state

2. measure its density and compare from the given list of densities

How would you determine volume?

Answer )volume=mass/volume

first measure the mass of the sample for least 5 times (for precision number of times of measurement can be increased)[note the measurements for plotting graph]

volume of the metal can be measured by measuring the water displaced by it ,when fully submerged in water.(Archimedes principle)

Take a graduated beaker with marked initial level of water,and then submerge the metal in it.Again mark the level of water after it is submerged .The difference in the levels of water gives you the volume of water displaced by the metal=volume of the metal(repeat 5 times) and note down the observations (to plot graph)

now density=average mass/av volume

for a graph ,plot volume measurements 5 times along x -axis and mass measurements along y-axis.

slope=(y2-y1)/(x2-x1)=difference of mass between two points/diff of volume b/w two points=density