Homework Help
Ask questions, doubts, problems and we will help you.
Ask questions which are clear, concise and easy to understand.
Why ionization energy is less for oxygen than nitrogen?

Answers:

This is due to an electron being added to an already half full orbital in oxygen, which results in electron electron repulsion, which will lower the ionisation energy. Nitrogen also has the added stability of a half filled shell of electrons in the 2p shell.
Thanks (0)
What is charge to radius ratio?
Does the first member of 13th group of p block element has small charge to radius ratio??

Answers:

Charge Radius Ratio: It is a measuring technique which describes the metallic character of elements.
According to charge/radius ratio, the element having c/r less than 7.0 are called as metallic, ane those elements which have charge /radius ratio greater than 7.0 are called as nonmetallic, whereas it has been seen that the element which has charge/radius ratio slightly greater than 7.0 are called as semimetals or more commonly called as semi conductor.
Thanks (0)
Why do you think there is no example of a gas  gas colloid?

Answers:

All gases are inherently miscible (completely soluble in each other), so by definition there is no such thing as a gasgas colloid.
Thanks (0)
Why the reaction of ester is intially slow and fast after sometime?

Answers:

Ester hydrolysis can be represented as: Ester + Water → Acid + Alcohol
The acid produced in the reaction acts as a catalyst and makes the reaction faster. Substances that act as catalysts in the same reaction in which they are obtained as products are known as autocatalysts.
Thanks (0)
What is hypertension and hypotension?

Answers:

Hypertension is a medical term for what we commonly call as high blood pressure. It is a health condition, but not exactly a disease, in which the blood pressure rises above the normal range. This is just the opposite of Hypotension or low blood pressure in which the blood pressure falls below the normal range.
Thanks (0)
differentiate between impact and nonimpact printers giving two points each

IMPACT PRINTERS
1. Impact printers operate by having an element strike the paper.
2. They are extremely slow, with printing just 10 characters per second.
NONIMPACT PRINTERS
1. The printheads of nonimpact printers do not strike the page.
2. They are somehow, faster than Impact Printers.
 Add Comment

Answers:
Evaluate : 1+i^{2}+i^{4}+i^{6}+.................+i^{2n}

Here i is stands for iota
 Add Comment

Answers:
If the units of length mass and force are taken as fundamental units then find the dimension of time?

Answers:
Why is electron gain enthalpy of flourine is less negative than that of chlorine?

Answers:

Electron gain enthalpy is defined as the enthalpy change associated with an isolated gaseous atom when it gains an electron to form its corresponding anion.
X_{(}_{g)} + e^{} > X^{} _{(g)}
General trend for variation of electron gain enthalpy down the group.
On moving down the group the atomic size as well as nuclear charge increases. But the effect of increase in atomic size is much more pronounced than that of nuclear charge. Thus , the additional electron feels less attraction with the result electron gain enthalpy becomes less negative on going down the group.
However in case of halogens , there happens to be an exception as given below.
F = 328 kj /mol
Cl = 349 kj /mol
Br = 325 kj /mol
I = 295 kj / mol
Electron gain enthalpy of F is less negative than Cl because of its smaller size. The additional electron in case of F will be added to 2p orbital , while in case of Cl it will go in the 3p orbital. as 2p orbital occupies a smaller region of space than that of 3p orbital, it will be more compact , due to which electron  electron repulsion would be more. Therefore, the incoming electron would be accepted with much less ease in case of F. Hence , its electron gain enthalpy is less negative than Cl.
Thanks (0)
how to get full marks in biology especially in the chapter herdiatary and evolution should we study that all practically

Answers:
Prove that (52√3)^{2} is irrational number?

Answers:

We will prove it in a same way as we prove that {tex} \sqrt{3}{/tex} is an irrational number..
Let us assume that {tex}({52\sqrt{3}})^2{/tex} is a rational number.
Then {tex}( {52\sqrt{3}})^2={p\over q}{/tex} where p and q are coprime.
{tex} =>{/tex} {tex}252×5×2{\sqrt 3}+(2{\sqrt 3})^2={p\over q}{/tex} [by using {tex}(ab)^2=a^22ab+b^2{/tex}
{tex}2520{\sqrt 3} +4×3={p\over q}{/tex}
{tex}2520{\sqrt 3}+12={p\over q}{/tex}
{tex}3720{\sqrt 3}={p\over q}{/tex}
{tex}37+{p\over q}=20{\sqrt3 }{/tex}
{tex}{37\over 20} +{p\over 20q}={\sqrt 3}{/tex}
Clearly L.H.S. is a sum of two rational number and therefore L.H.S is rational.
So {tex}{\sqrt 3}{/tex} is a rational number.
But we know that {tex}{\sqrt3}{/tex} is an irrational number.So our assumption is wrong.
Hence {tex}({52\sqrt{3}})^2{/tex}is an irrational number.
Thanks (0) 
prove (52 root3)^{2 = }2520root 3+12=p/q consider it as rational first
but solving it we get that root 3 could be represented as rational but it is irrational number thus our assumption that (52 root 3)^{2}was wrong and hence it is irrational
Thanks (0)
Q. Difference between xt curve and vt curve?
Q. Can xt curve give acceleration graph?

Answers:
Features of alluvial soil

Answers:

alluvial soil  a finegrained fertile soil deposited by water flowing over flood plains or in river beds. alluvial deposit, alluvial sediment, alluvium, alluvion  clay or silt or gravel carried by rushing streams and deposited where the stream slows down. Alluvial soil as a whole is very fertile. These soils contain adequate proportion of Potash, Lime and Phosphoric acid. Silk, clay, gravel and sand the main constituents of alluvial soil. It is commonly found in riverbed and flood plains.
Thanks (1)
Why electric flux of cylindrical vessel is zero at the end?

Answers:
Write balanced chemical equation for the following statements:
(i) NaOH solution is heated with zinc granules.
(ii) Excess of carbon dioxide gas is passed through lime water.
(iii) Dilute sulphuric acid reacts with sodium carbonate.
(iv) Egg shells are dropped in hydrochloric acid.
(v) Copper (II) oxide reacts with dilute hydrochloric acid.

Answers:

(i)2NaOH(aq) + Zn(s) > Na_{2}ZnO_{2 }+ H_{2(g)}
(ii) CO_{2} + Ca(OH)_{2} > CaCO_{3} (milky)+H_{2}O
CaCO_{3} + H_{2}O +CO_{2} > Ca (HCO_{3})_{2} (milkiness disappears)
(iii) H_{2}SO_{4} + Na_{2}CO_{3} > Na_{2}SO_{4} + H_{2}O +CO_{2}
(iv) CaCO_{3} + 2HCl > CaCl_{2} +H_{2}O+CO_{2}
(v) CuO + 2HCl > CuCl_{2} + H_{2}O
Thanks (0)
Full form of DVC.

Damodar Valley Corporation
 Add Comment

Answers:

Damodar Valley Corporation
Thanks (0)
Which phrases did the narrator use to describe the arrival of the night ?

Answers:
Can we use cramer rule to solve determinant questions in board exams as it is not given in ncert book? ? ?

Answers:

its not cramer rule its cremer rule or cross multiplication method which is the most easiest way to solve LE in 2 variables and it is given in ncert book if not your book has some problem or you have it
Thanks (0)
A body moves with velocity 5m/s under acceleration 2m/s find the time taken to travel a distance of 20m???

Answers:

U=5
a=2
S=20
Apply second eq of motion .
Thanks (1)
What were the most precious possession of Jim and Della

Answers:
The writer gives details of Jim's flat.pick out the details.

Answers:
How did Della save her one dollar and eightyseven cents?

Answers:
Among magnesium silicon and aluminum.. Which has highest ionisation energy?

Answers:

Ionization enthalpy is the energy required to remove the most loosely bound electron from an isolated atom (in the gaseous state) for one mole of an element.
Among magnesium, silicon and aluminum, silicon has highest ionisation energy. Magnesium, aluminum and silicon are the elements of the third period in the periodic table. As one moves from left to right in the periodic table, there is a regular increase in the magnitude of ionization enthalpy of elements, with a few exceptions. E.g. The ionization enthalpy of Al (aluminium) is lower than that of Mg (magnesium). The first ionization enthalpy of magnesium is higher because the electron is removed from the fully filled 's' orbital.
The first ionisation enthalpies of magnesium, aluminum and silicon are given below:
Period Element First ionisation enthalpy Element First ionisation enthalpy Element First ionisation enthalpy 3 Magnesium 737 kJ mol^{1} Aluminum 577 kJ mol^{1} Silicon 786 kJ mol^{1} Thanks (0)
How does the law of DMU affect the law of demand?

Answers:

Law of DMU states that as we consume more and more unit of a particular commodity each successive unit give lesser and lesser satisfaction so as the consumer demand more quantity of a particular commodity utility from it falls which is a reason that consumer value extra units at a lesser price.
Thanks (0)
What is ment by biological magnification

Answers:

The increase in the concentration of a toxicant at successive higher trophic levels.
Thanks (0) 
1. Biological magnification is also known as Biomagnification.
2. It is the increase in concentration of certain chemicals like pesticides (ex. DDT) and heavy metals (ex. Mercury) in the tissue of living being at each successive level of food chain.
3. The concentration of these chemicals is highest in the top trophic level.
Thanks (0)
In chapter introduction to trignometry how we will know where we have to which formula

Answers:

understand the concpt apply it
Thanks (0)
What is the integration of under root sinx

Answers:
http://mycbseguide.com/downloads/cbseclass12geography/1863/cbseimportantquestions/6/
Is this for 201718?because I'm learning these imp ques only for boards exams

Answers: