Tags Chemistry

Chemistry

Get insights from 6.9k questions on Chemistry, answered by students, alumni, and experts. You may also ask and answer any question you like about Chemistry

Follow Ask Question

6.9k

Questions

Discussions

Active Users

Followers

New answer posted

3 months ago

Chemistry Class 12th

150g of acetic acid was contaminated with 10.2g ascorbic acid $(C_{6} H_{8} O_{6})$ to lower down its freezing point by (x * 10^-¹)°C. The value of x is _________. (Nearest integer)

(Given K_f = 3.9 K kg mol^-¹; molar mass of ascorbic acid = 176 g mol^-¹]

0 Follower 4 Views

Raj Pandey

Contributor-Level 9

$m = \frac{w * 1000}{m o l e c u l a r w t * w_{s o l v e n t}} = \frac{10.2 * 1000}{176 * 150}$

$= \frac{10200}{176 * 150} = 0.386$

$Δ T_{f} = K_{f} * m$

3.9 * 0.386

$∴ x * 1 0^{- 1} = 15.05 * 1 0^{- 1}$

Ans = 15

0 0

New answer posted

3 months ago

Chemistry Chemistry Chemical Bonding and Molecular Structure

The number of paramagnetic species among the following is

B₂, Li₂, C₂, $C_{2}^{-}$ , $O_{2}^{- 2}$ , $O_{2}^{+}$ and $H e_{2}^{+}$ .

0 Follower 5 Views

Raj Pandey

Contributor-Level 9

$B_{2} = σ_{1 s}^{2} σ_{1 s}^{* 2} σ_{2 s}^{2} σ_{2 s}^{* 2} π_{2 p x}^{1} = π_{2 p y}^{1} \to$ Paramagnetic

$\begin{array}{l} L i_{2} = σ_{1 s}^{2} σ_{1 s}^{* 2} σ_{2 s}^{2} \to D i a m a g n e t i c \\ C_{2} = σ_{1 s}^{2} σ_{1 s}^{* 2} σ_{2 s}^{2} σ_{2 s}^{* 2} π_{2 p x}^{2} \equiv π_{2 p y}^{2} \to D i a m a g n e t i c \\ C_{2}^{-} = σ_{1 s}^{2} σ_{1 s}^{* 2} σ_{2 s}^{2} σ_{2 s}^{* 2} π_{2 p x}^{2} \equiv π_{2 p y}^{2} σ_{2 p z}^{1} \to P a r a m a g n e t i c \end{array}$

$O_{2}^{- 2} = σ_{1 s}^{2} σ_{1 s}^{* 2} σ_{2 s}^{2} σ_{2 s}^{* 2} σ_{2 p z}^{2} π_{2 p x}^{2} \equiv π_{2 p y}^{2} π_{2 p x}^{* 2} \equiv π_{2 p y}^{* 2}$ Diamagnetic

$O_{2}^{+} = σ_{1 s}^{2} σ_{1 s}^{* 2} σ_{2 s}^{2} σ_{2 s}^{* 2} σ_{2 p z}^{2} π_{2 p x}^{2} \equiv π_{2 p y}^{2} π_{2 p x}^{* 1} \equiv π_{2 p y}^{0} \to$ Paramagnetic

$H e_{2}^{+} = σ_{1 s}^{2} σ_{1 s}^{* 1} \to$ Paramagnetic

$∴$ Paramagnetic molecules are $= B_{2}, C_{2}^{-}, O_{2}^{+}, H e_{2}^{+}$

0 0

New answer posted

3 months ago

Chemistry Class 12th

An element M crystallises in a body centred cubic unit cell with a cell edge of 300 pm. The density of the element is 6.0g cm^-³. The number of atoms in 180g of the element is_________* 10²³ (Nearest integer)

0 Follower 2 Views

Raj Pandey

Contributor-Level 9

B.C.C structure

a = 300 pm = 300 * 10^-¹² m

d = 6g/cm³

z = 2

$d = \frac{Z * M}{a^{3}}$

$6 = \frac{2 * A}{{(300 * 1 0^{- 10})}^{3}} = \frac{2 * A}{27 * 1 0^{- 24}}$

$∴ A t o m s o f M$ = 3.69 * 6.022 * 10²³

...more

B.C.C structure

a = 300 pm = 300 * 10^-¹² m

d = 6g/cm³

z = 2

$d = \frac{Z * M}{a^{3}}$

$6 = \frac{2 * A}{{(300 * 1 0^{- 10})}^{3}} = \frac{2 * A}{27 * 1 0^{- 24}}$

$∴ A t o m s o f M$ = 3.69 * 6.022 * 10²³

= 22.22 * 10²³

the nearest integer = 22

less

0 0

New answer posted

3 months ago

Chemistry Class 11th

In the given reaction,

X + Y + 3Z XYZ₃

If one mole of each of X and Y with 0.05 mol of Z gives compound XYZ₃. (Given: Atomic masses of X, Y and Z are 10, 20 and 30 amu, respectively.) The yield of XYZ₃ is_____________g.

0 Follower 9 Views

Raj Pandey

Contributor-Level 9

x + y + 3z = xyz₃

1 mole 1 mole 0.05 mole

$∴ n_{x} = 1$

$n_{y} = 1$

$n_{z} = \frac{0.05}{3} = 0.0167$ here z is limiting reagent.

$? \frac{0.05}{3}$ mole z gives 1 mole xyz₃

mass of xyz₃ = n * molecular mass

= $\frac{0.05}{3} * (10 + 20 + 3 * 30) a . m . u .$

= 0.5 * 4 = 2g

0 0

New answer posted

3 months ago

Chemistry Ncert Solutions Chemistry Class 11th

The geometry around boron in the product 'B' formed from the following reaction is

$B F_{3} + N a H \overset{450 K}{\to} A + N a F$

A + NMe₃ $\overset{}{\to} B$

0 Follower 2 Views

Raj Pandey

Contributor-Level 9

$2 B F_{3} + 6 N a H \to B_{2} H_{6} + 6 N a F$

$B_{2} H_{6} + 2 \overset{?}{N} {(M e)}_{3} \to 2 H_{3} B \leftarrow : N {(M e)}_{3}$

0 0

New answer posted

3 months ago

Chemistry Ncert Solutions Chemistry Class 11th

Choose the correct order of density of the alkali meals:

0 Follower 1 View

Raj Pandey

Contributor-Level 9

Density of metal a very specific and depends upon many factors.

Li ® 0.53 gm/cm³

Na ® 0.97 gm/cm³

K ® 0.86 gm/cm³

Rb ®1.53 gm/cm³

Cs ® 1.90 gm/cm³

0 0

New answer posted

3 months ago

Chemistry Redox Reactions

The reaction of H₂O₂ with potassium permanganate in acidic medium leads to the formation of mainly.

0 Follower 3 Views

Raj Pandey

Contributor-Level 9

$2 M n O_{4}^{-} + 6 H^{+} + 5 H_{2} O_{2} \to 2 M n^{2 +} + 8 H_{2} O + 5 O_{2}$

0 0

New answer posted

3 months ago

Chemistry Ncert Solutions Chemistry Class 12th

The compound(s) that is (are) removed as slag during the extraction of copper is:

(A) CaO

B) FeO

C) Al₂O₃

(D) ZnO

(E) NiO

Choose the correct answer from the options given below.

0 Follower 2 Views

Raj Pandey

Contributor-Level 9

$F e O + \underset{(A c i d i c f l u x)}{S i O_{2}} \to \underset{(S l a g)}{F e S i O_{3}}$

0 0

New answer posted

3 months ago

Chemistry Class 12th

The IUPAC nomenclature of an element with electronic configuration [Rn] 5f¹⁴6d¹7s² is:

0 Follower 1 View

Raj Pandey

Contributor-Level 9

IUPAC nomenclature of element with atomic no. 103 is uniltrium

0 0

New answer posted

3 months ago

Chemistry Ncert Solutions Chemistry Class 12th

Match the List-I with List-II

List-I	List-II
(A) N₂(g) + 3H₂(g) ® 2NH₃(g)	(I) Cu
(B) CO(g) + 3H₂(g) ® CH₄(g) + H₂O(g)	(II) Cu/ZnO – Cr₂O₃
(C) CO(g) + H₂(g) ® HCOH(g)	(III) Fe_xO_y + K₂O + Al₂O₃
(D) CO(g) + 2H₂(g) ® CH₃OH(g)	(IV) Ni

Choose the correct answer from the options given below:

0 Follower 1 View

Raj Pandey

Contributor-Level 9

Uses of catalyst is very specific for a particular reaction.

0 0

Get authentic answers from experts, students and alumni that you won't find anywhere else

On Shiksha, get access to

66k Colleges
1.2k Exams
681k Reviews
1800k Answers

Community GuidelinesUser Points System

QuestionsDiscussionsTags

Need guidance on career and education? Ask our experts

Your Question

Chemistry

Questions

Discussions

Active Users

Followers

All

Discussions

Unanswered Questions

Share Your College Life Experience