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Answer:</h2>
The magnesium ribbon, <u>D. It forms a material to cast the tool mark</u>.
<h2>
Explanation:</h2>
When a magnesium ribbon is burnt in the presence of oxygen it gives out strong light and heat is produced. Apart from it, it leads to the production of substance called as magnesium oxide which is formed as the product due to the reaction of magnesium with the oxygen present in the air.
Tool marks are the mark which is created by tools while using them. In order to identify or locate them castes made up of magnesium oxide is utilized. When this is pasted on the suspected area, the tool mark of the suspected tool gets pasted on it.
Answer: There are five significant figures in 865,010.
Explanation:
When a degree of accuracy is stated by each digit present in a mathematical figure then it is called a significant figure.
Rules for counting significant figures is as follows.
- Any non-zero digits and zeros present between a non-zero figure are counted. For example, 3580009 has seven significant figures.
- Trailing zeros are counted in a non-zero figure. For example, 0.00250 has three significant figures.
- Leading zeros are not counted. For example, 0.0025 has two significant figures.
So, in the given figure 865010 has five significant figures and the trailing zero will not be counted.
Thus, we can conclude that there are five significant figures in 865,010.
In chemical reactions the reactants are on the left side of the equation and the product are on the right
Answer:
Total percent of magnesium in sample = 25.5%
Explanation:
Given:
Mass of magnesium = 24 gram
Mass of chlorine = 70 gram
Find:
Total percent of magnesium in sample = ?
Computation:
Total mass of sample = Mass of magnesium + Mass of chlorine
Total mass of sample = 24 gram + 70 gram
Total mass of sample = 94 gram
Total percent of magnesium in sample = [Mass of magnesium / Total mass of sample]100
Total percent of magnesium in sample = [24/94]100
Total percent of magnesium in sample = [0.255]100
Total percent of magnesium in sample = 25.5%
<h2>Answer:</h2>

<h2>Explanations</h2>
The complete balanced equation for the given reaction is expressed as;

Given the following parameters
Mass of CH4 = 5.90×10^−3 g = 0.0059grams
Determine the moles of methane

According to stoichimetry, 1 mole of methane produces 2 moles of water, hence the moles of water required will be:

Determine the mass of water produced

Therefore the mass of water produced from the complete combustion of 5.90×10−3 g of methane is 1.33 * 10^-2grams