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What is the difference between actinoids and lanthanoids.

Posted by Hardeep Singh 8 years, 3 months ago

1 answers

Nisha Beniwal 8 years, 3 months ago

Lanthanoid r involve in the filling of 4 f orbital wheras actinoid r fill 5f orbital, lathanoid r non radioactive in nature except promethium wheras actinoid r radioactive in nature

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Please explain the in text 11.5 second part. Pg no 325

Posted by Bio Tech 8 years, 3 months ago

CBSE > Class 12 > Chemistry

2 answers

Bio Tech 8 years, 3 months ago

Explain 2nd part nicely

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Aryan Vyas 8 years, 3 months ago

(1) in 1st apply markovnikov rule and then propan 2-ol will obtain (2) in 2nd the reactant with given NaBh4 and form mehyl ethanoate (3) in 3rd the reactant react with given NaBH4 and form 2-Methyl butan-1-ol.

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Neha garg r u a pcb student

Posted by Bio Tech 8 years, 3 months ago

CBSE > Class 12 > Chemistry

0 answers

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Show thermodynamically adsorption is exothermic process

Posted by Tauhid Mohd 8 years, 3 months ago

CBSE > Class 12 > Chemistry

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How do we prepare ether?write its reaction?

Posted by Bethel Modi 8 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Neha Garg 8 years, 3 months ago

By willminson's synthesis: by reacting alkyl halide and sodium alcoxide.

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Which type of synthetic detergents are biodegradable and why?

Posted by Vineit Kumar Gupta 8 years, 3 months ago

CBSE > Class 12 > Chemistry

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Explain why Ni and Pt are paramagnetic and Pd is dimagnetic in nature.

Posted by Prerit Yadav 8 years, 3 months ago

CBSE > Class 12 > Chemistry

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Convert chloroform into chloropicrin

Posted by Ankit Mittal 8 years, 3 months ago

CBSE > Class 12 > Chemistry

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A binarysolid (AB) has the rock salt structure. if the edge length is 400 picometre and the radius of cation is 75 picometre then the radius of anion will be

Posted by Prabhat Thakur 8 years, 3 months ago

CBSE > Class 12 > Chemistry

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Do conversion from methyl bromide to acetone reaction

Posted by Asif Khan 8 years, 3 months ago

CBSE > Class 12 > Chemistry

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Henry's law

Posted by Bio Tech 8 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Neha Garg 8 years, 3 months ago

At constt. temp. partial vapour pressure is directly proportional to the mole fraction

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What is Na3AlF6? And its use

Posted by Akshay Tomar 8 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

N V 8 years, 3 months ago

it is commonly known as cryolite. Aluminum is obtained from pure alumina by hall heroult process by electrolysis In this process pure alumina(Al2O3) is mixed with cryoliteto reduce the melting point of mixture and increase its conductivity It makes alumina a good conductor which is normally a poor conductor.

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Why glass is considered as super cold liquid

Posted by Ankit Upadhyay 8 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Nisha Beniwal 8 years, 3 months ago

Bcoz it has tendency to flow...

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Time for half change for a first order reaction is 25 minutes. What time will be required for 99% reaction ?

Posted by Harman Bhullar 8 years, 3 months ago

CBSE > Class 12 > Chemistry

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Which investigatory project could be made related to metellurgy

Posted by Yash Mangal 8 years, 3 months ago

CBSE > Class 12 > Chemistry

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What is fajan's rule

Posted by Anmol Sharma 8 years, 3 months ago

CBSE > Class 12 > Chemistry

2 answers

Nisha Beniwal 8 years, 3 months ago

More covalent nature -more polarizing power :fajan rule

2Thank You

Vineit Kumar Gupta 8 years, 3 months ago

It talks about covalent nature

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IUPAC names of major halides ?

Posted by Sagar Agrawal 8 years, 3 months ago

CBSE > Class 12 > Chemistry

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What is fajan rule

Posted by Harsh Tyagi 8 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Yash Mangal 8 years, 3 months ago

It is related to the size of ions interacting in a ionic compound. It is generally defined to show the ionic and covalent nature percentage in the compound. When the size of cation and anion are comparable the n the ionic character dominates and if the size difference is more then the covalent character shows its effect. For a detailled answer follow chemical bonding topic from a good book eg.arihant

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What are puseudohalogen compound,????

Posted by Shashi Kant Thakur 8 years, 3 months ago

CBSE > Class 12 > Chemistry

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Suggest a reason for the large difference in the boiling points of butanol and butanal although they have same solubility in water?

Posted by Megha Budhouliya 8 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Shailja Shukla 8 years, 3 months ago

Because butanol is slightly polar( having an OH grp) so there r strong intermolecular forces between butanol.... I HOPE U Understand...

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Posted by Hasrat Ali 8 years, 3 months ago

CBSE > Class 12 > Chemistry

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Which of the following reasons is sn1type x Bond C2 h5 Bond h Bond CS2

Posted by Hasrat Ali 8 years, 3 months ago

CBSE > Class 12 > Chemistry

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Hoffmann degradation

Posted by Anand Raj 8 years, 3 months ago

CBSE > Class 12 > Chemistry

2 answers

Neha Garg 8 years, 3 months ago

When amide is treated with alkyl bromide then amines are formed with 1 less carbon than reactant

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Yashika Jain 8 years, 3 months ago

Reaction when no. Of carbon has to be less after conversion in amine chapter

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How to conclude syllabii of chemistry so that confusions less

Posted by Ajay Rana 8 years, 3 months ago

CBSE > Class 12 > Chemistry

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formula of adiphic acid

Posted by Anurag Soni 8 years, 3 months ago

CBSE > Class 12 > Chemistry

2 answers

N V 8 years, 3 months ago

and it is adipic not adiphic acid

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N V 8 years, 3 months ago

HO2C (CH2)4 CO2H also writen as C6H10O4

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I had saved some chemistry offline content....and it is not displaying now. What to do????

Posted by Twisha Mistry 8 years, 3 months ago

CBSE > Class 12 > Chemistry

0 answers

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aniline is weak base than cyclohexylamine

Posted by Himanshi Bhandari 8 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Neha Garg 8 years, 3 months ago

Because carbon atom directly attached to NH2 group is sp2 hybridised. Due to electron withdrawing nature of benzene ring electron density on N-atom decreases. Hence, basic character also decreases

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Difference between air pollution and water pollution

Posted by Rahul Kumar 4 years, 9 months ago

CBSE > Class 12 > Chemistry

1 answers

Sia ? 4 years, 9 months ago

<center>Air Pollution</center>	<center>Water Pollution</center>
<center>General Overview</center>
Air pollution is caused by harmful particulates	Water pollution is usually caused by effluents
<center>Effects on Health</center>
Usually, air pollution affects the respiratory system, causing difficulty in breathing, COPD, respiratory infections, asthma and even lung cancer. It can also affect existing cardiac conditions.	Water usually affects the digestive system, but can also affect other body systems depending upon the type of pollutant or pathogen present in the water.
<center>Anthropogenic Sources (Man-made)</center>
Anthropogenic sources of air pollution includes fossil fuel-based power stations, factories, furnaces, burning biomass such as wood, dung or crop waste. Vehicles running on fossil fuels also contribute to air pollution. Moreover, products such as paints, varnish as well as chemical aerosols cause air to be polluted	Anthropogenic sources range from industrial effluents and storm drain (from construction sites and such). Other sources of water pollution includes agricultural run off as well as industrial accidents such as oil spills.
<center>Natural Sources</center>
Natural sources of air pollution include dust from areas with little to no vegetation. Cattle are also a surprising source of air pollution as they emit large quantities of methane. Wild fires and volcanoes also pump out significant particulates and smoke into the atmosphere, contributing to air pollution.	Natural sources of water pollution includes oxygen-depleting substances such as plant matter (grasses and leaves). Eutrophication is another process that can also induce detrimental effects on an aquatic ecosystem.
<center>Methods of Measurements</center>
Air quality is usually measured with the Air Quality Index (AQI). Alternatively, the quality of air can also be measured using Particulate Matter (PM). PM_2.5 is a microscopic particle which is 2.5 microns wide. When significant levels of PM_2.5 particles are present in the atmosphere, it can cause haze, an indicator of bad air quality.	Water quality can be measured using a variety of methods. Some of the most common are Coloured or Chromophoric Dissolved Organic matter (CDOM), Conductivity, Salinity and TDS Monitoring, Measuring Dissolved Oxygen Levels. pH and KH Testing (carbonate hardness).