Hey
Sorry, But There Is No 7th Element in group two. only six which is Radium.
~Spades15
Weight of sodium thiosulfate = 76.148 - 8.2
= 67.948 g.
Concentration of the solution = 67.948 / 172.7
= 0.393 g / mL. to the nearest thousandth . (answer).
I think the best answer is the last option. A scatter plot is the appropriate type of graph for the student to use to show the percent samples per group. This plot is somewhat similar to line graphs. However, they are use for a specific purpose which is to show the relationship between two parameters. In this case, the correlation between pH and the percent of samples.
The products will be 
<h3>Chemical reactions</h3>
Zn is higher than hydrogen in the reactivity series. Thus, it will be able to displace hydrogen from the acid.
The equation of the reaction becomes: 
Hydrogen gas is released as a result. In fact, it is one of the ways of preparing hydrogen gas in the laboratory.
More on chemical reactivity can be found here: brainly.com/question/9621716
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