Answer: Green is 550 nm and blue is 470 nm
We can see here that the both measurements are accurate. This is the true because the both values are in the correct number of significant figures.
<h3>What is density?</h3>
The term density has to do with the ratio of the mass to the density of the object. We know that the accuracy of a measurement has a lot to do with the number of significant figures in the measurement. In this case, we are told that two students in a lab are asked to calculate the density of a block with a mass of 31.0 g; they are not told how many digits to round their measurements. Student A finds length to be 2 cm width to be 4 cm and height 8 cm. Student B finds the length to be 2.65 cm, width to be 4.20 cm, and height to be 8.35 cm.
For the first student, the density is obtained as;
Density = mass/ volume
= 31.0 g/ 2 cm * 4 cm * 8 cm
= 0.5 g/cm^3
For the second student;
Density = mass/ volume
= 31.0 g/2.65 cm * 4.20 cm * 8.35 cm
= 0.33 g/cm^3
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Answer: The given reaction redox reaction not a combustion reaction.
Explanation:
Redox Reaction is defined chemical reaction in which oxidation and reduction takes place simultaneously. In Oxidation addition of oxygen occurs and in reduction addition of hydrogen occurs.
Potassium is getting oxidized by addition of oxygen.
Water us reduced to hydrogen gas by removal of oxygen
Combustion reaction is defined as chemical reaction in which burning of a chemical compound or element takes place in presence of oxygen occurs.
In the given reaction, oxygen molecule is absent which means this reaction is not combustion reaction.
Hence ,the given reaction redox reaction not a combustion reaction.
There is one significant figure as a significant figure is any number other than 0
if it was 120 then it would be 2
