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Explain chemical reaction .

Posted by Prince Kumar 4 years, 2 months ago

CBSE > Class 10 > Science

4 answers

Preeti Dabral 4 years, 2 months ago

Chemical reaction, a process in which one or more substances, the reactants, are converted to one or more different substances, the products. ... A chemical reaction rearranges the constituent atoms of the reactants to create different substances as products.

Abhishek $Kr 4 years, 2 months ago

Chemical reaction :-It is a process in which one or more substances react with each other and form another compound or element which is different chemical properties

Akshat Holland Minettee 4 years, 2 months ago

A chemical reaction is a chemical change in which two or more substances called reactants reactants react with each other to form a new substance or substances called products. Eg - 2Mg + O2 ------> 2MgO

Susri Namrata Deep 4 years, 2 months ago

It is a process in which one or more substance form a new substance and it's can't reserved by physical method.

ANSWER

The statement that is most correct about the readings of ammeters A1 , A2, A3 are connected in the following circuit ( current read by each are shown i ¹, i 2 , i 3 respectively.

Posted by Aarti Belwal 4 years, 2 months ago

CBSE > Class 10 > Science

1 answers

Preeti Dabral 4 years, 2 months ago

L1 L2 and L3 are the statements that is most correct about the readings of an ammeter

ANSWER

State ohms law and write mathematical equations

Posted by Ritik Kumar Gupta 4 years, 2 months ago

CBSE > Class 10 > Science

4 answers

Preeti Dabral 4 years, 2 months ago

Ohm's law states that the voltage or potential difference between two points is directly proportional to the current or electricity passing through the resistance, and directly proportional to the resistance of the circuit. The formula for Ohm's law is V=IR.

Om Tiwari 4 years, 2 months ago

Ohm ' s law states that the potential difference of two points is directly proportional to the current flowing through it . V is directly proportional to I V=I × R

......... ....... 4 years, 2 months ago

In 1827, The German scientist George Simon Ohm gave a relationship between potential difference and electric current.Ohm's law states that the potential difference across the uniform cross section area of a wire is directly proportional to flow of charges through its cross section area, provided that the temperature remains constant.

Sachin Kumar 4 years, 2 months ago

Ohm's law state the potential difference between two points is directly proportional to current passing through resistance and directly proportional to the resistance at the constant temperature

ANSWER

How are the evolution of gas indicate in a chemical equation

Posted by Juhi Kumari 4 years, 2 months ago

CBSE > Class 10 > Science

1 answers

Parth Surmare 4 years, 2 months ago

The evolution of a gas in a chemical equation is indicated by an arrow facing upwards....

ANSWER

What is finger like projection

Posted by Cc Cc 4 years, 2 months ago

CBSE > Class 10 > Science

2 answers

Dhana Lakshmi S 4 years, 2 months ago

Villi is finger like projection found in small intestine

Shreyash Pandey 4 years, 2 months ago

Villi

ANSWER

Find the nature position of the image object size 1cm and its distance is 15cm and focal length

Posted by Bakkar Ali 4 years, 2 months ago

CBSE > Class 10 > Science

1 answers

Preeti Dabral 4 years, 2 months ago

The given mirror is a concave mirror thus sign convention it's focal length will be negative.

This here
f = -10 cm
u = -15cm
h(height of object) = 1cm

we have to find
size , nature , position of image formed .

Thus using mirror equation :-
1/f = 1/u+1/v
=>1/v = 1/f-1/u
=> 1/v = -1/10+1/15
=> 1/v = -1/30
=> v = -30 { thus image will be formed beyond center
Now magnification
m = -(v/u) = h'/h
m = -(-30/-15)
=> m = -2
HENCE the image formed will be real and inverted and magnified.

Now m = h'/h
2 = h'/1
=> h' = 2cm
hence the size of the image will be doubled

ANSWER

Who is the first sciencetist who done toilet on moon

Posted by Aakash Giri 4 years, 2 months ago

CBSE > Class 10 > Science

3 answers

Nishant Singh 4 years, 2 months ago

Question koi puchta hai to usko Gali Nahi dete

Nishant Singh 4 years, 2 months ago

Bhai Buzz Aldrin your question is very mind blowing

Priya Kumari 4 years, 2 months ago

Pgal hai kya bc

ANSWER

ravi has taken bread in his breakfast explain the process of digestion in his ailementary canal after eating food

Posted by Akshat Kumar Mour 4 years, 2 months ago

CBSE > Class 10 > Science

1 answers

Sumesh Sharma 4 years, 2 months ago

Bread contain starch, it will convert in maltose in mouth through saliva amylase

ANSWER

What happens when silver chloride is exposed to sunlight ?Give one practical application of this reaction .write the equation also.

Posted by Atiqur Rahman 4 years, 2 months ago

CBSE > Class 10 > Science

2 answers

Atiqur Rahman 4 years, 2 months ago

Plz give full answers

Sumesh Sharma 4 years, 2 months ago

It will decompose in silver and chlorine

ANSWER

Identify the substance that are oxidized and the substance that are reduced to the following reaction. 1. Na(s)+o2(g)-->Na2o 1.Cuo(s)+H2(g)-->Cu(s)+H2o(l).

Posted by Atiqur Rahman 4 years, 2 months ago

CBSE > Class 10 > Science

2 answers

Abhishek $Kr 4 years, 2 months ago

In this reaction, Na (sodium) is oxidised and CuO (Copper oxide) is reduced.

Sumesh Sharma 4 years, 2 months ago

Na _oxidation ,O2 reduced, ___cuo reduced and H2 oxidised

ANSWER

Transfer the following statement into chemical equation and then balance them. a)Hydrogen gas combines with nitrogen to form ammonia. b)potassium reacts with water to give potassium hydroxide and hydrogen gas.

Posted by Atiqur Rahman 4 years, 2 months ago

CBSE > Class 10 > Science

2 answers

Sumesh Sharma 4 years, 2 months ago

2K+2h2o=2koh+2h2

Affin J 4 years, 2 months ago

1) hydrogen combines with nitrogen gas to form ammonia 3H2 (gas) + N2 (GAS) = 2NH3

ANSWER

What is combination reaction? Give an example with chemical equation.

Posted by Vivek Kumar Singh 4 years, 2 months ago

CBSE > Class 10 > Science

5 answers

Sia ? 4 years, 2 months ago

In combination reactions, two or more substances combine to form a new compound. Only one product is obtained in such reactions. The reactants in such reactions can be elements as well as compounds.
For Example, Calcium oxide reacts with water to produce calcium hydroxide.

Abhishek $Kr 4 years, 2 months ago

Combination reaction :-A chemical reaction in which one or more substances combines and formed a single substance is called combination reaction. In this reaction, two elements react with each other and form a single compound. Examples:- CaO +H2O - Ca(OH)2+heat Mg +O2 - 2 MgO

Anmol Preet 4 years, 2 months ago

A chemical reaction in which two or more substances (elements or compounds) combine to form s single new compound is called combination reaction. ??? ??????? :- 2K + Cl2 ----> 2KCl

Rishi Raj 4 years, 2 months ago

The reaction in which two or more substances combine to form a new substance are called combination reaction. for example: 2Mg + O2 --> 2MgO

Sumesh Sharma 4 years, 2 months ago

When two or more compound react to form a single products, ex__ magnisium reacts with oxygen to give magnisium oxide

ANSWER

Why is respiration considered as an exothermic reaction. Explain

Posted by Atiqur Rahman 4 years, 2 months ago

CBSE > Class 10 > Science

1 answers

Nitya Pv 4 years, 2 months ago

Exothermic reactions release heat or energy.When you or we breath out,breath is warmer.This is happened for respiration reaction of our body. Carbolydrates present in food are broken down to form glucose.This glucose combines with oxygen in the cells of our body and provides energy.This reaction is known as respiration.hence,respiration is considered as an exothermic reaction.

ANSWER

Write down the observations which indicate the occurrence of the chemical reaction?

Posted by Atiqur Rahman 4 years, 2 months ago

CBSE > Class 10 > Science

2 answers

Rishi Raj 4 years, 2 months ago

The five main observations which indicate the occurrence of the chemical reaction:- ☆ Change in state. ☆ Formation of precipitate. ☆ Change in colour. ☆ Evolution of a gas. ☆ Change in temperature.

Nitya Pv 4 years, 2 months ago

The following observations in an activity may suggest that a chemical reaction has taken places. ∙ Change in state ∙ Change in colour ∙Evolution of a gas ∙ Change in temperature

ANSWER

Why do we balance the chemical equation ?

Posted by Atiqur Rahman 4 years, 2 months ago

CBSE > Class 10 > Science

1 answers

Sia ? 4 years, 2 months ago

A chemical equation must be balanced because the Law of Conservation of matter must be hold good during a chemical equation.

Balancing of equation is necessary because atoms are neither created nor destroyed during a chemical equation.

Thus, the balancing of chemical equation is based on law of conservation os mass/matter.

There are two commonly used methods for balancing chemical equations :-

Hit-and-trial Method
Partial equation Method

ANSWER

Why does the colour of copper sulphate solution change when an iron nail is dipped into it????

Posted by Atiqur Rahman 4 years, 2 months ago

CBSE > Class 10 > Science

1 answers

Nitya Pv 4 years, 2 months ago

When an iron nail immersed in the solution of copper sulphate than iron displaces copper from the solution of copper sulphate because iron is more reactive than copper. Therefore copper sulphate solution colour changes from blue to pale green.

ANSWER

Name the type of reaction in which energy is absorbed .plz gives answers

Posted by Atiqur Rahman 4 years, 2 months ago

CBSE > Class 10 > Science

2 answers

Abhishek $Kr 4 years, 2 months ago

Answer :- Endothermic reaction

Nitya Pv 4 years, 2 months ago

The type of reaction which energy is absorbed is endothermic reaction

ANSWER

Fe2o3+2Al-->Al2o3+2fe. The above reaction is an example of which type of reaction.

Posted by Atiqur Rahman 4 years, 2 months ago

CBSE > Class 10 > Science

1 answers

Saurabh Shrivastava 4 years, 2 months ago

displacement reaction

ANSWER

Give the characteristics test for 1.Co2 2.No2 3.So2 4.so3

Posted by Baishna Ballabi Mishra 4 years, 2 months ago

CBSE > Class 10 > Science

1 answers

Sia ? 4 years, 2 months ago

CO₂ gas : If CO₂ gas is passed to lime water [Conc. Calcium hydroxide solution], it turns milky white.
The gas is brown in colour. It has a pungent smell. It changes blue litmus paper to red.
Sulphur dioxide is a odorless and pungent gas. Sulphur dioxide gas turns acidified potassium dichromate solution from orange to green colour.
Sulphur trioxide is often formed when sulphur dioxide is oxidised. This chemical compound can occur in different forms more widely in a white crystalline solid.

ANSWER

What are the gases released,when ferrous sulphate crystal is heatered.write down the observation made.Also write the balanced chemical reaction.

Posted by Baishna Ballabi Mishra 4 years, 2 months ago

CBSE > Class 10 > Science

1 answers

Dhana Lakshmi S 4 years, 2 months ago

Equation: FeSO4 GIVES WHEN HEATED IS Fe2O3+SO2+SO3.. Balanced form:2FeSO4 GIVES Fe2O3+SO2+SO3... The gases released are Sulphur dioxide and Sulphur trioxide....

ANSWER

A brown colour gas 'Q' formed by the decomposition of a compound 'P' when the aquors form of 'P' is passed through potassium iodide solution.A yellow colour precipitate formed 'R'.Identify P,Q,R. write down the reactions involved in the above process

Posted by Baishna Ballabi Mishra 4 years, 2 months ago

CBSE > Class 10 > Science

1 answers

......... ....... 4 years, 2 months ago

The compound P which is lead nitrate on heating decomposes into lead monoxide,nitrogen gas which gives out brown fumes and hydrogen gas is liberated. The brown colour gas is nitrogen fumes. When the aqueous solution of lead nitrate reacts with potassium iodide then the yellow precipitate lead iodide is formed along with the formation of potassium nitrate.

ANSWER

Numericals:- an object 6cm in size is placed at 10cm in front of the concave mirror of focal length is 20 cm what distance from the mirror should be screen placed to obtain a sharp image? find the nature and the size of the image?

Posted by Pankhuri Sharma 4 years, 2 months ago

CBSE > Class 10 > Science

1 answers

Sia ? 4 years, 2 months ago

Consider the situation shown in the figure below which also includes the coordinate system.
Here, u=−10cm
f=−20cm
Subtituting in the equation,
1/v + 1/u = 1/f, we get
v = +20cm
Thus, the image is formed 20 cm behind the mirror, magnification +2, erect and virtual.

ANSWER

Draw a ray diagram for when an object placed at C at a concave mirror

Posted by Pankhuri Sharma 4 years, 2 months ago

CBSE > Class 10 > Science

1 answers

Sia ? 4 years, 2 months ago

ANSWER

State the law of reflection of light?

Posted by Pankhuri Sharma 4 years, 2 months ago

CBSE > Class 10 > Science

4 answers

Om Tiwari 4 years, 2 months ago

1=》The angle of incidence is always equal to the angle of reflection 2=》The incident ray ,the reflected ray and the normal lie on the same plane.

Anmol Preet 4 years, 2 months ago

There are two laws of reflection :- ????? ??? :- The incident ray, the normal to the reflecting surface at the point of incidence and the reflected ray, all lie in the same plane. ?????? ??? :- The angle of incidence and angle of reflection are equal and lie on opposite sides of the normal.

Md Aftab Alam 4 years, 2 months ago

There are two laws of reflection 1 The angle of incidence is equal to the angle of reflection. 2 the incident Ray the reflected ray and the normal at the point of incidence all lie in the same plane

Nitya Pv 4 years, 2 months ago

They are two laws of reflection First law - According to the law of reflection of light the angle of reflection is always equal to angle of incidence Second law - The incident ray , reflected ray ,and the normal (at the point of incidence) all lie on the same plane

ANSWER

define the principal focus of concave mirror and principal axis of concave mirror

Posted by Pankhuri Sharma 4 years, 2 months ago

CBSE > Class 10 > Science

1 answers

Nitya Pv 4 years, 2 months ago

When a parallel rays strikes the concave mirror after reflection the ray passes through a point or meet at one point.This point is called principal focus of concave mirror

ANSWER

The resistance of wire is r ohm what will be its new resistance it is stretched to a times it's original length

Posted by Ashish Singh 4 years, 2 months ago

CBSE > Class 10 > Science

0 answers

ANSWER

Which gas is produce by the action of dilute hydrochloric acid on zinc granules?

Posted by Atiqur Rahman 4 years, 2 months ago

CBSE > Class 10 > Science

1 answers

Rishabh Kothari 4 years, 2 months ago

Zn +2HCl--> ZnCl2+ H2 Hydrogen gas is evolved

ANSWER

What do copper vessel lose their shine when exposed to air.? plz give answer

Posted by Atiqur Rahman 4 years, 2 months ago

CBSE > Class 10 > Science

1 answers

Rishabh Kothari 4 years, 2 months ago

Copper reacts with oxygen in air to form copper oxide which is black in colour. So, it turns black and lose its shine

ANSWER

How can we know that given chemical equations are strong or weak?

Posted by Satyam Choudhary 4 years, 2 months ago

CBSE > Class 10 > Science

2 answers

Rishabh Kothari 4 years, 2 months ago

By using pH scale. It is used to measure whether that substances are acidic or basic

Punita Palak 4 years, 2 months ago

the strength of an acid or a base can be measured using a pH scale. pH stands for 'power of hydrogen'. pH is a scale used for measuring the hydrogen ion concentration in a solution. This scale ranges from values 0 to 14. The higher the concentration of hydrogen ions, the lower is the pH value. •So if th pH is less than 7 (0to 3) then it is acidic and strong acid and high H+ions. •if pH is 3. to 6. It is weak acid so low H+ions. •pH 7 is nutral •pH 8 to 11 weak base and low OH- ions •pH 11 to 14 strong base and high OH-ions In order to find the strength of an acid or a base, a universal indicator is used, A universal indicator is a mixture of several indicators, and it shows a different colour for differen hydrogen ions concentrations in a solution, Since the hydrogen ion concentration of a solution Indicated by its pH value, each colour change shown by the universal indicator corresponds to a value on the pH scale.

ANSWER

What action taken by Male and Female body to reproduce?

Posted by Janvi Verma 4 years, 2 months ago

CBSE > Class 10 > Science

0 answers

ANSWER

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