Significant Figures

Q. $1L$ of milk weighs $1.035$ kg. The butter fat it contains to the extent of $4\%$ by volume has a density of $875kg/m^3.$ Find the density of the fat-free 'skimmed' milk.
($1m^3={10}^{3}L$)

1. $942kg/m^3$
2. $1124kg/m^3$
3. $1042kg/m^3$
4. $1242kg/m^3$

Q.

A $6.5$ molal solution of $\mathrm{KOH}(\mathrm{aq}.)$ has a density of $1.89gc{m}^{-3}$.The molarity of the solution is __________ $mold{m}^{-3}$. (Round off to the Nearest Integer).

Q.

If the density of a solution is $3.12gm{L}^{-1}$, the mass of 1.5 mL solution in significant figures is .......

(a) 4.7 g (b) $4680\times {10}^{-3}g$ (c) 4.680 g (d) 46.80 g

Q.

Express 35 mm in cm, m, and km

Q.

What is $3.5\mathrm{k}$ in rupees?

Q.

What is the name given to the number 6.022 x ${10}^{23}$

Q.

What is the value of 200 lb in kilograms?

Q. Conc. $H_{2}S{O}_4$ has a density of 1.98 gm /ml and is $98\%H_{2}S{O}_4$ by weight. Its normality is

1. 2N
2. 19.8N
3. 39.6N
4. 98N

Q.

What is the expanded form of $100$?

Q.

How many significant figures should be present in the answer of the following calculations ?

$\frac{2.5\times 1.25\times 3.5}{2.01}$

Q.

How many significant figures are there in this

=0.0125 + 0.7864 + 0.0215

Q. Given the numbers: 161 cm, 0.161 cm, 0.0161 cm. The number of significant figures for the three numbers is

1. 3, 3 and 4 respectively
2. 3, 4 and 4 respectively
3. 3, 4 and 5 respectively
4. 3, 3 and 3 respectively

Q.

The mass to charge ratio (m/e) for a univalent cation is 1.5 $\times$ ${10}^{-8}$ Kg/c. Find mass of the atom.

1. 2.4 $\times$ ${10}^{-24}$g

2. 2.4 $\times$ ${10}^{-27}$g

3. 2.4 $\times$ ${10}^{-24}$g

4. 2.4 $\times$ ${10}^{-19}$g

Q.

The number of significant figures in the numbers $4.8000\times {10}^4$and $48000.50$ are respectively.

1. $5$ and $6$

2. $5$ and $7$

3. $2$ and $7$

4. $2$ and $6$

Q.

The number $9.6506531,$ when rounded off to $4$ places of decimal, gives $\_\_\_\_\_\_$.

Q. How many significant figures are present in $0.010100\times {10}^3$?

1. 5
2. 7
3. 3
4. 10

Q. How many moles of $HI{O}_4$ are consumed by Sucrose?

1. 2
2. 3
3. 4
4. 1

Q.

Find H.C.F. of $625$ and $250$ by division method.

Q. What is the number of significant figures obtained after addition of $4.523,2.3$ and $6.24$?

1. Four
2. Five
3. Three
4. Two

Q.

The scientific notation for $700$ is_______________.

Q. How many significant figures are present in $7\times 2.232$?

1. $5$
2. $3$
3. $4$
4. $1$

Q. What is the molecular mass of glucose $C_6{H}_{12}{O}_6$ molecule up to 6 significant figures?

1. 180.162
2. 180.162
3. 180.16
4. 180.16

Q. If the density of a solution is $3.12gm/m{l}^{-1}$, the mass of $1.5ml$ solution in significant figures is:

1. $4680\times {10}^{-3}g$
2. $4.680g$
3. $4.7g$
4. $46.80g$

Q. 105 ml of pure water at $4^{\circ }C$ is saturated with $N{H}_3$ (g) producing a solution of density 0.9 gm/ml. If this solution Contain $30\%$ of $N{H}_3$ by mass, the total volume of solution is -

1. 250 ml
2. 125 ml
3. 166.67 ml
4. 111.11 ml

Q.

1. Two
2. Three
3. Five
4. Four

Q. The value of $200lb$ in kilograms is

1. $440kg$
2. $100kg$
3. $90.9kg$
4. $400kg$

Q. What will be the answer in appropriate significant figures as a result of addition of 3.0223 and 5.041?

1. 80.633
2. 8.0633
3. 8.063
4. 806.33

Q. Express the following in scientific notation: (i) $0.0024$, (ii) $600.0$

Q.

In the following questions a statement of Assertion (A) followed by a statement of Reason (R) is given. Choose the option out of the choices given below in each question

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.

(a) Both A and R are true and R is correct explanation of A.

(b) Both A and R are true but R is not the correct explanation of A

(c) A is true but R is false.

(d) Both A and R are false.

Q. Express $0.006006$ in scientific notation with three significant digits.

1. $6.01\times {10}^{-3}$
2. $6.006\times {10}^{-3}$
3. $6.00\times {10}^{-3}$
4. $6.0\times {10}^{-3}$