Advertisements
Advertisements
Question
If the density of a solution is 3.12 g mL–1, the mass of 1.5 mL solution in significant figures is ______.
Options
4.7 g
4680 × 10–3 g
4.680 g
46.80 g
Advertisements
Solution
If the density of a solution is 3.12 g mL–1, the mass of 1.5 mL solution in significant figures is 4.7 g.
Explanation:
Density of a solution = `"Mass of solution"/"Volume of solution"`
3.12 g mL–1 = `x/(1.5 mL)`
∴ `x = 3.12 xx 1.5`
`x` = 4.68 g
The number of significant figures in the product of a multiplication or division should equal the number of figures in the calculation's least precise phrase. This term's degree of precision is 1.5.
As a result, the needed response should include two significant figures.
4.68 g, for example, should be rounded up to 4.7 g.
APPEARS IN
RELATED QUESTIONS
How many significant figures are present in the 126,000?
Round up the following upto three significant figures:
2808
You are given a thread and a metre scale. How will you estimate the diameter of the thread?
The length, breadth, and thickness of a rectangular sheet of metal are 4.234 m, 1.005 m, and 2.01 cm respectively. Give the area and volume of the sheet to correct significant figures.
Precise measurements of physical quantities are a need of science. For example, to ascertain the speed of an aircraft, one must have an accurate method to find its positions at closely separated instants of time. This was the actual motivation behind the discovery of radar in World War II. Think of different examples in modern science where precise measurements of length, time, mass etc. are needed. Also, wherever you can, give a quantitative idea of the precision needed.
A man walking briskly in rain with speed v must slant his umbrella forward making an angle θ with the vertical. A student derives the following relation between θ and v: tan θ = v and checks that the relation has a correct limit: as v →0, θ → 0, as expected. (We are assuming there is no strong wind and that the rain falls vertically for a stationary man). Do you think this relation can be correct? If not, guess the correct relation.
It is a well known fact that during a total solar eclipse the disk of the moon almost completely covers the disk of the Sun. From this fact and from the information you can gather from examples 2.3 and 2.4, determine the approximate diameter of the moon.
Just as precise measurements are necessary in science, it is equally important to be able to make rough estimates of quantities using rudimentary ideas and common observations. Think of ways by which you can estimate the following (where an estimate is difficult to obtain, try to get an upper bound on the quantity):-
the wind speed during a storm
A large ball 2 m in radius is made up of a rope of square cross-section with edge length 4 mm. Neglecting the air gaps in the ball, what is the total length of the rope to the nearest order of magnitude?
Which of the following has the highest number of significant figures?
The radius of the circle is 3.12 m. Calculate the area of the circle with regard to significant figures.
Write a short note on the following.
Rounding - off
How many significant figures should be present in the answer of the following calculations?
`(2.5 xx 1.25 xx 3.5)/2.01`
Assertion (A): Significant figures for 0.200 is 3 where as for 200 it is 1.
Reason (R): Zero at the end or right of a number are significant provided they are not on the right side of the decimal point.
The sum of the numbers 436.32, 227.2 and 0.301 in appropriate significant figures is ______.
Which of the following measurements contains exactly two significant figures?
How many significant figures are there in the number 0.001405?
The radius of Earth is expressed as 0.64 × 10⁷ m in scientific notation. What is its order of magnitude and number of significant figures?
Which of the following statements is correct about significant figures and accuracy?
