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I have a problem "i can't memorize the ion's chargers" any tips which help"s me out...??

Posted by Divyang Parmar 6 years ago

CBSE > Class 10 > Science

0 answers

ANSWER

Explain the mechanism of cleaning action of soap

Posted by Anuj Singh 6 years ago

CBSE > Class 10 > Science

1 answers

Sahil Yadav 6 years ago

The dirt present on cloths is organic and insoluble in water. Therefore it cannot be removed by only washing with water when shops are dissolved in water their hydrophobic end attach themselves to the dirt and remove it from the cloth. Then the molecules of soap arrange themselves in micelle formation and trap the dirt at the centre of cluster. These micelles remain suspended in water. Hence the dust particles are easily rinsed away the water.

ANSWER

Why the object is placed in only the principle axis

Posted by Nirmal Mandal 6 years ago

CBSE > Class 10 > Science

0 answers

ANSWER

C chemical reaction of citric acid and potassium permanganate

Posted by Sikendra Yadav 6 years ago

CBSE > Class 10 > Science

1 answers

Ijhar Khan 6 years ago

Colour yellow

ANSWER

What happens when sodium absorb moisture from air air and write a chemical equation for it

Posted by Poonam Pandey 6 years ago

CBSE > Class 10 > Science

3 answers

Kumkum Sarswat 6 years ago

Sodium is a very reactive metal. When it reacts with the moisture present in air it catches fire. It is a highly exothermic reaction.......

Yogita Ingle 6 years ago

When sodium reacts with moist air it forms Sodium Hydroxide and hydrogen.
Reaction:
H₂+ 2H₂O → 2NaOH + H₂

Ravinder Dhaiya 6 years ago

Na +H2o =na2o +h2 + heat , huge ammount of heat is evolved

ANSWER

Write the preparation of bliching powder

Posted by Rojalin Sahu 6 years ago

CBSE > Class 10 > Science

2 answers

Yogita Ingle 6 years ago

<div class="cooked">

Preparation of Bleaching Power :

Chlorine gas is produced during electrolysis of aqueous sodium chloride.
This chlorine gas is used for the manufacture of bleaching powder.
Bleaching powder is produced by the action of a chlorine on slaked lime.
Ca(OH)₂ + Cl₂ → CaoCl₂ + H₂O
Uses of Bleaching Power :
It is used for bleaching cotton and linen in the textile industry for bleaching wood pulp in paper industry for bleaching washed clothes in laundry.
Used as an oxidizing agent in many chemical industries.
Used for disinfecting drinking water to make it free of germs.
Used as a reagent in the preparation of chloroform.

</div>

Prîyåñshus Råj 6 years ago

Ca(OH)2+Cl2-----------CaoCl2+HCl

ANSWER

What property do all the elements in the same column of the periodic table as boron having common

Posted by Prarthana Paramesh 6 years ago

CBSE > Class 10 > Science

1 answers

Yogita Ingle 6 years ago

The property that all the elements in the same column of the periodic table as boron have is: “the same number of valence electrons (3). Hence, they all have valency equal to 3.”

Boron is derived from the Arabic word “buraq”. “It belongs to the 13th group of the p block element”. Boron is metalloid in nature. All of them in the group has “3 electrons in the outermost shell”.

ANSWER

What changs can you make in your habits to become more environment friendly ?

Posted by Karan Kumar 6 years ago

CBSE > Class 10 > Science

4 answers

Kumkum Sarswat 6 years ago

5 Rs....

Jay Prakash Mishra 6 years ago

By making my personality more friendly with nature as I won't create pollution

Apoorva ..... 6 years ago

Follow all five R rules Use bicycle for short distances Use grahmin seva bus Plant more trees Use chlorine to dirty water to make it pure for drinking

Yogita Ingle 6 years ago

1. Reduce food waste
2. Save water
3. Make your own cleaning products
4. Save electricity
5. Drive less to save petrol
6. Reuse containers
7. Start a garden
8. Minimise wastage of paper
9. Stop using plastic bags
10. Minimise using synthetic products instead of natural.

ANSWER

Calculate the resistance of a copper wire 1km long and 0.50mm diameter if the resistivity of the wire is 1.7×10^-8ohm metres

Posted by Gurneet Kaur 6 years ago

CBSE > Class 10 > Science

2 answers

Gurneet Kaur 6 years ago

Thank u

Yogita Ingle 6 years ago

Diameter d = 0.50 mm

Diameter d={tex}2 \times radius {/tex}

Radius r = {tex}\frac{d}{ 2}{/tex}

Radius r = {tex}\frac{0.50}{ 2} {/tex}

Radius r = 0.25 mm = 0.00025 m

Resistivity{tex} \rho=1.7 \times 10^{-8} \text { ohm } m{/tex}

Resistance R= {tex} {\rho\times\frac{\text{length}}{\text{area}}}{/tex}

{tex}\begin{aligned} R &=\rho \times \frac{l}{A} \\ R &=1.7 \times 10^{-8} \times \frac{1000}{\pi r^{2}} \\ R=& \frac{1.7 \times 10^{-5}}{3.14 \times 0.00025 \times 0.00025} \\ R=& \frac{1.7 \times 10^{3}}{3.14 \times 6.25} \\ R &=\frac{1700}{19.625} \\ & {R=86.6 \mathrm{ohm}} . \end{aligned}{/tex}

ANSWER

Which pole of a solenoid has been shown in the adjoining figure?

Posted by Mayank Priyadarshi 6 years ago

CBSE > Class 10 > Science

1 answers

Aman Mishra 6 years ago

North

ANSWER

The length of wire is doubled. By what factor does the resistance change?

Posted by Anand Nagapure 6 years ago

CBSE > Class 10 > Science

3 answers

Kumkum Sarswat 6 years ago

Resistance also become double........

Deepak Kumar 6 years ago

R is directly proportion to l

Aadya Singh ? 6 years ago

The resistance is directly proportional to the length of wire. So, when the length of wire is doubled, then the resistance also gets doubled.

ANSWER

Explain the nature of covalant bond using the bond formation in CH3Cl ?

Posted by Tushar Sindhi 6 years ago

CBSE > Class 10 > Science

3 answers

Kumkum Sarswat 6 years ago

Single covalent bond.....

Unnati Agarwal 6 years ago

Single covalent bond

Yogita Ingle 6 years ago

Carbon has four electron in its outermost shell and needs to gain or loss four electrons to attain noble gas configuration. To overcome this, carbon shares each of the four electrons with each of the three hydrogen atoms and one chloride atom. The bond that are formed by sharing electrons are known as covalent bond.

ANSWER

What are the contons under which we can convert a alcohol into carboxylic acid

Posted by Priyank Yadav 6 years ago

CBSE > Class 10 > Science

1 answers

Tushar Sindhi 6 years ago

By- alk. Kmno4

ANSWER

What change in colour is observed when white silver chloride is left exposed to sunlight? What type of chemical reaction is this?

Posted by Anand Nagapure 6 years ago

CBSE > Class 10 > Science

4 answers

Kumkum Sarswat 6 years ago

Greyish black Photo decomposition reaction.....

Yashvi Mehta 6 years ago

Silver chloride when exposed to sunlight turns greyish black. This reaction is called autochemical decomposition reaction. 2AgCl --> 2Ag + Cl2

Yogita Ingle 6 years ago

When white Silver chloride exposed to sunlight it produces to black metallic colured Silver along with liberation of Chlorine gas.
2AgCl → 2Ag + Cl_{<font size="2">2</font>}
This is a photodecomposition reaction.

Tushar Sindhi 6 years ago

Photo decomposition reaction.

ANSWER

Why carbon and carbon do not make four bond between them

Posted by Taruna Chundawat 6 years ago

CBSE > Class 10 > Science

2 answers

Yashvi Mehta 6 years ago

Carbon and carbon can make 4 covalent bonds between them. Carbon can have 680 other cabon atoms attatched to it.

Priyank Yadav 6 years ago

Because carbon has valency of 4 and its difficult to gain or loose 4 electron so he forms bond but with each other they can't make 4 bond between them as they requires HYDROCARBON OR A FUNCTIONAL GROUP TO FORM COMPOUNDS

ANSWER

What is illustration

Posted by Bharat Shukla 6 years ago

CBSE > Class 10 > Science

0 answers

ANSWER

what is the use of HCL in stomach

Posted by Avni Khanna 6 years ago

CBSE > Class 10 > Science

8 answers

Arun Kirar 6 years ago

It kills the microbes which may enter our body through food..

Kumkum Sarswat 6 years ago

Provides acidic medium for the working of pepsin enzyme and also kills the germs.......

Ijhar Khan 6 years ago

Digestion in food molecules break

Priyanshu Nassa 6 years ago

It kills the germs which enter into our body along with food and it provide a acidic medium for the action of pepsin enzyme

Leepaxi Diwan? 6 years ago

It help to kill the bacteria of food which were present in food which we eat

Tushar Sindhi 6 years ago

It helps in body to kill the bacteria.

Gaurav Seth 6 years ago

The roles of HCL in our stomach are as follows :

1) It provides acidic nature .

2) It activates the enzyme pepsin .

3) It kills the germs that may have entered into our stomach with food.

In other words,

Hydrochloric acid gets mixed with food and kills the bacteria present in food. It also destroys the structure of proteins so that the enzymes can digest them easily. Hydrochloric acid also creates acidic conditions necessary for the action of the enzyme pepsin. It activates pepsin to act on proteins.

Aadya Singh ? 6 years ago

It makes the food acidic in nature and kills the bacteria that may enter in stomach with the food...

ANSWER

Why carbon is most important element than other

Posted by Priyanshu Sinha 6 years ago

CBSE > Class 10 > Science

1 answers

Aadya Singh ? 6 years ago

Because it is able to bond in different ways . It can form many compounds that are essential for life. It is the primary components of biomolecules . Important ones are protein, lipids, carbohydrates, etc...

ANSWER

What change in colour is observed when white AgCl is left exposed to sunlight

Posted by Rsjdonpro Jambale 6 years ago

CBSE > Class 10 > Science

5 answers

Arun Kirar 6 years ago

Black..,

Tushar Sindhi 6 years ago

White silver chloride exposed in sunlight then it produces the black metalic coloured.

Abhishek Kumar 6 years ago

Grey

Gaurav Seth 6 years ago

When white Silver chloride exposed to sunlight it produces to black metallic colured Silver along with liberation of Chlorine gas.
2AgCl → 2Ag + Cl₂
This is a photodecomposition reaction.

Shreya ... 6 years ago

Black

ANSWER

Pre board exam 2019 class 10 marking scheme

Posted by Chirag Rohilla 6 years ago

CBSE > Class 10 > Science

1 answers

Shreya ... 6 years ago

Same as board marking scheme.

ANSWER

What is presbiopia

Posted by Deep Tech 6 years ago

CBSE > Class 10 > Science

2 answers

Arun Kirar 6 years ago

It is the defect in which a person is not able to see nearby and far off objects.It generally occurs at old age..

Aadya Singh ? 6 years ago

Presbyopia is that defect of vision due to which an old person cannot see the nearby objects clearly due to loss of power of accommodation of eye.

ANSWER

Dot structure of methanal

Posted by Akshita Dhiman 6 years ago

CBSE > Class 10 > Science

3 answers

Aadya Singh ? 6 years ago

Aadya Singh ? 6 years ago

Sorry....ye mathanol ka h...

Aadya Singh ? 6 years ago

ANSWER

Two bulbs are connected in parallel to each other and to a voltage supply. If resistance of the bulbs is R1 andR2 (R1>R2). Across which more power is consumed 1.R1 2. R2 3. Same across R1 andR2 4. None of these

Posted by Riya Shrivastva 6 years ago

CBSE > Class 10 > Science

0 answers

ANSWER

What are formulas of compounds

Posted by Mukul Saini 6 years ago

CBSE > Class 10 > Science

0 answers

ANSWER

What is cyst? briefly?

Posted by Vikas Saini 6 years ago

CBSE > Class 10 > Science

2 answers

Muskan Taya 6 years ago

Cyst is a layer on spores When spores are fall down then this layer protect to absorb the moisture

Rishabh Tadwal 6 years ago

The outer layer of the plamodium is know that cyst

ANSWER

What is cyst

Posted by Mayuri Ambekar 6 years ago

CBSE > Class 10 > Science

2 answers

Priyanshu Gautam 6 years ago

A abnormal, usually noncancerous growth filled with liquid or a semisolid substance, sometime causing pain.

Shreya ... 6 years ago

Cyst can be referred as abnormal growth of tissue. A cyst is a closed sac of tissue filled with gas, fluid or semisolid material.

ANSWER

Define 1 dioptre of power of a lens ?

Posted by Jansi Lakhpati 6 years ago

CBSE > Class 10 > Science

2 answers

Miss. 1234 6 years ago

1 dioptre of power of a lens is defined as the unit of measuring the power of optical lens Or curved mirror which is equal to the reciprocal of the focal length. The focal length is measured in the meter. 1 dioptre is equal to 1/m where m is the focal length. Basically dioptre is the SI unit of optical power of the lens.

Anjali Anil 6 years ago

1 dioptre is a power of lens which is defined as per m.

ANSWER

How does the resistance of wire vary with area of cross section

Posted by Arun Kumar 6 years ago

CBSE > Class 10 > Science

2 answers

Aashish Garhwal 6 years ago

When area of crocc section decreases resistance increases and vice versa

Miss. 1234 6 years ago

Resistance is inversely proportional to area of cross section. larger will be the area lower will be the resistance and vice versa.

ANSWER

What is the name of CH³-OH.

Posted by Mahendra Kumar 6 years ago

CBSE > Class 10 > Science

5 answers

Vikas Saini 6 years ago

Methanol

Aashish Garhwal 6 years ago

Methanol

Miss. 1234 6 years ago

Methanol

Akanksha Maurya 6 years ago

Methanol

Abhinandh Krishna. R 6 years ago

Methanol

ANSWER

Define absolute refractive index and express it mathematically

Posted by Its Angruuu 6 years ago

CBSE > Class 10 > Science

1 answers

Vikas Saini 6 years ago

It is define as in the three medium of relative refractive index is vaccum,1st medium,2nd medium

ANSWER

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