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The most abundant elements by mass in the body of a healthy human adult are : Oxygen (61.4%); Carbon (22.9%), Hydrogen (10.0%); and Nitrogen (2.6%). The weight (in kg) which a 75 kg person would gain if all $\dpi{100} ^{1}H$ atoms are replaced by $\dpi{100} ^{2}H$ atoms is :   Option: 1 7.5 Option: 2 10 Option: 3 15 Option: 4 37.5

Given that

Mass of the person = 75 kg

Mass of 1H1 present in person = 10% of 75 kg = 7.5 kg

Since Mass of 1H2 is double the Mass of 1H1

So, Mass of 1H2 will be in person = 2 X 7.5 kg =15 kg

Thus, increase in weight = 15 - 7.5 = 7.5 kg

Therefore, Option (1) is correct

The correct order of the atomic radii of C, Cs, Al and S is : Option: 1 Option: 2 Option: 3 Option: 4

In a period from left to right the effective nuclear charge increases because the next electron fills in the same shell. So the atomic size decrease.

- wherein

The attraction between the outer electrons and the nucleus increases as the atomic radius decreases in a period.

- wherein

Size of atom and ion in a group -

In a group moving from top to the bottom the number of shell increases.So the atomic size increases.

- wherein

As we know that

From Left to right in a period size decreases and when going down the group size increases

Therefore, Option(2) is correct

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The IUPAC symbol for the element with atomic number 119 would be: Option: 1 uue Option: 2une Option: 3 unh Option: 4 uun

Nomenclature of elements with atomic number >100 -

The name is derived directly from the atomic number of the element using the following numerical roots:

0 = nil

1 = un

2 = bi

3 = tri

5 = pent

6 = hex

7 = sept

8 = oct

9 = enn

Eg:

 Atomic number Name Symbol 101 Mendelevium (Unnilunium) Md (Unu) 102 Nobelium (Unnilbium) No (Unb)

-

uue

1  1  9

Un Un ennium

Therefore, Option(1) is correct.

The ammonia $(NH_{3})$ released on quantitative reaction of 0.6g, urea $(NH_{2}CONH_{2})$ with sodium hydroxide $(NaOH)$ can be neutralised by: Option: 1 200 ml of 0.2 N HCl Option: 2200 ml of 0.4 N HCl Option: 3100 ml of 0.1N HCl Option: 4100 ml of 0.2N HCl

2 × mole of Urea = mole of $NH_{3}$ ........(1)
mole of $NH_{3}$ = mole of $HCl$ ........(2)
$\therefore$ mole of HCl = 2 × mole of Urea

mole of HCl =$2\times \frac{0.6}{60}=0.02mol$ ...(i)

[We know , mole = M X V = N X n X V]

$\mathrm{100 \ ml\times 0.2N\times 1=0.02\ mol}$ ...as (i).

Therefore, Option(4) is correct.

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Mischmetal is an alloy consisting mainly of :Option: 1 lanthanoid metalsOption: 2 actionoid and transition metalsOption: 3 Lanthanoid and actionoid metalsOption: 4 actionoid metals

Mischmetal is an alloy of lanthanoid metals with Fe.

It consists of a lanthanoid metal (~95%) and iron (~5%) and traces of S, C, Ca, and Al.

Therefore, the correct option is (1).

The average molar mass of chlorine is $35.5\: g\: mol^{-1}.$ The ratio of $^{35}Cl\; to\; ^{37}Cl$ in naturally occurring chlorine is close to :  Option: 1 4:1Option: 2 3:1Option: 3 2:1Option: 4 1:1

Given,

The average molar mass of chlorine is $35.5\: g\: mol^{-1}.$

Let , the ratio of $^{35}Cl\; to\; ^{37}Cl$ in naturally occurring chlorine is close to x : y

Now, we know

$\text { Av. molar mass }=\frac{\mathrm{n}_{1} \mathrm{M}_{1}+\mathrm{n}_{2} \mathrm{M}_{2}}{\left(\mathrm{n}_{1}+\mathrm{n}_{2}\right)}$

So,

$35.5=\frac{x \times 35+y \times 37}{x+y}$

$1.5 y=-0.5 x$

$\frac{x}{y}=\frac{3}{1}$

Therefore, the correct option is (2).

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The minimum number of moles of O2 required for complete combustion of 1 mole of propane and 2 moles of butane is ______

Combustion reaction of 1 mole of propane and 2 moles of butane-

So, Total required mol of O2 = 5 + 13 = 18.

Ans = 18

If a person is suffering from the deficiency if nor-adrenaline, what kind of drug can be suggested ?  Option: 1 Anti-inflammatoryOption: 2 AntidepressantOption: 3 AntihistamineOption: 4 Analgesic

Non-adrenaline is a neurotransmitter. If nor-adrenaline is low, a person may suffer from depression. Hence, an antidepressant drug is suggested.

Anti-depressant → drug, which enhances the mood.

Therefore, the correct option is (2).

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The following molecules act as an : Option: 1 AntidepranantOption: 2 Anti-bacterial  Option: 3 AntisepticOption: 4 Anti-histamine

Brompheniramine works by blocking the action of histamine, which causes allergic symptoms.

Hence, it acts as an antihistamine.

Therefore, Option(3) is correct.

The mass of ammonia in grams produced when 2.8 kg of dinitrogen quantitatively reacts with 1 kg of dihydrogen is_________Option: 1 3400Option: 2 -Option: 3 -Option: 4 -

Given,

2.8 kg of dinitrogen quantitatively reacts with 1 kg of dihydrogen.

From above, the mole of ammonia = 0.2 kMol

So, mass of ammonia = mole X molar mass

mass of ammonia = 0.2 (kMol ) X 17 (g/Mol)

mass of ammonia = 3.4 kg = 3400 g

Ans = 3400