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Ask QuestionPosted by Islam Zehen 3 years, 11 months ago
- 2 answers
Tanisha . 3 years, 11 months ago
Gaurav Seth 3 years, 11 months ago
The first law of motion implies that things cannot start, stop, or change direction all by themselves. It requires some force from the outside to cause such a change. This property of massive bodies to resist changes in their state of motion is called inertia. Newton’s first law is also known as the law of inertia.
Newton’s 1st law states that a body at rest or uniform motion will continue to be at rest or uniform motion until and unless a net external force acts on it.
Posted by Archita Priyadarshani 3 years, 11 months ago
- 2 answers
Roshani Pal 3 years, 11 months ago
Yogita Ingle 3 years, 11 months ago
In solids atoms are closely spaced in comparison to those of liquids and gases. That’s why density of solid is higher.
Posted by Diya Gupta 3 years, 11 months ago
- 4 answers
Yogita Ingle 3 years, 11 months ago
The metals like Sodium ( Na) and Potassium ( K ) are easily cut with the help of a knife. So, sodium and potassium are not lustrous.
Posted by Muskan Mishra 3 years, 11 months ago
- 4 answers
Posted by Likhith Kannadiga 3 years, 11 months ago
- 2 answers
Shivam Mor 3 years, 11 months ago
Yogita Ingle 3 years, 11 months ago
| Homogenous Mixture | Heterogeneous mixture |
| They have uniform compositions | They have non-uniform compositions. |
| The components of homogeneous mixtures are not physically distinct. | They have no visible boundaries of separation between the constituents. |
|
They have no visible boundaries of separation between the constituents |
They have visible boundaries of separation between the constituents. |
| Examples: Alloys, Solution of salts in water etc. | Examples: Mixture of sand and common salt, Mixture of sand and water etc. |
Posted by Likhith Kannadiga 3 years, 11 months ago
- 4 answers
Sumit Balesra 3 years, 11 months ago
Sarah Mehrotra 3 years, 11 months ago
Jai Ghosh 3 years, 11 months ago
Posted by Gulshan Kumar 3 years, 11 months ago
- 1 answers
Yogita Ingle 3 years, 11 months ago
The net force is defined as is the sum of all the forces acting on an object. Net force can accelerate a mass. Some other force acts on a body either at rest or motion. The net force is a term used in a system when there is a significant number of forces.
Posted by Jahanvi Chauhan 3 years, 11 months ago
- 1 answers
Meghna Thapar 3 years, 11 months ago
The antibodies destroy the antigen (pathogen) which is then engulfed and digested by macrophages. White blood cells can also produce chemicals called antitoxins which destroy the toxins (poisons) some bacteria produce when they have invaded the body. Antibodies are proteins produced by the body to neutralize or destroy toxins or disease-carrying organisms. Antibodies are disease-specific. For example, measles antibody will protect a person who is exposed to measles disease, but will have no effect if he or she is exposed to mumps.
Posted by Andriya George 3 years, 11 months ago
- 2 answers
Sumit Balesra 3 years, 11 months ago
Yogita Ingle 3 years, 11 months ago
The postulates of this theory may be stated as follows:
- Matters are composed of very tiny particles called atoms.
- These particles are too small to see and cannot be created or destroyed in a chemical reaction.
- Atoms of a specified element are identical in mass and chemical properties.
- Atoms of different elements have different masses and chemical properties.
- Atoms combine in the ratio of small whole numbers to form compounds.
- The relative number and kinds of atoms are constant in a given compound.
Posted by Aashi Agrawal 3 years, 11 months ago
- 4 answers
Pawan Kumar Pal 3 years, 11 months ago
Muskan Mishra 3 years, 11 months ago
Posted by Andriya George 3 years, 11 months ago
- 4 answers
Yogita Ingle 3 years, 11 months ago
There are five basic laws of chemical combination that govern the chemical combinations of elements:
1. Law of Conservation of Mass
In simple terms, this law states that matter can neither be created nor destroyed. In other words, the total mass, that is, the sum of the mass of reacting mixture and the products formed remains constant. Antoine Lavoisier gave this law in the year 1789 based on the data he obtained after carefully studying numerous combustion reactions.
2. Law of Definite Proportions
Joseph Proust, a French chemist stated that the proportion of elements by weight in a given compound will always remain exactly the same. In simple terms, we can say that irrespective of its source, origin or its quantity, the per cent composition of elements by weight in a given compound will always remain the same.
3. Law of Multiple Proportions
This law states that if two elements combine to form more than one compound, the masses of these elements in the reaction are in the ratio of small whole numbers. This law was given by Dalton in the year 1803.
4. Gay Lussac’s Law of Gaseous Volumes
In 1808, Gay Lussac gave this law based on his observations. This law states that when gases are produced or combine in a chemical reaction, they do so in a simple ratio by volume given that all the gases are at the same temperature and pressure. This law can be considered as another form of the law of definite proportions. The only difference between these two laws of chemical combination is that Gay Lussac’s Law is stated with respect to volume while the law of definite proportions is stated with respect to mass.
5. Avogadro’s Law
Avogadro proposed this law in the year 1811. It stated that under the same conditions of temperature and pressure, an equal volume of all the gases contains an equal number of molecules. This implies that 2 litres of hydrogen will have the same number of molecules as 2 litres of oxygen given that both the gases are at the same temperature and pressure.
Posted by Moksha Sahu 3 years, 11 months ago
- 2 answers
Yogita Ingle 3 years, 11 months ago
A sound is a form of energy, just like electricity, heat or light. Let’s examine some sources of sounds like a bell. When you strike a bell, it makes a loud ringing noise. Now, instead of just listening to the bell, put your finger on the bell after you have struck it. Can you feel it vibrating? This is the key to the sound. It is even more evident in guitars and drums. You can see the wires vibrating every time you pluck it. When the bell or the guitar stops vibrating, the sound also stops.
Posted by Pradeep Mehta 3 years, 11 months ago
- 1 answers
Posted by Suchitra Sen 3 years, 11 months ago
- 1 answers
Gaurav Seth 3 years, 11 months ago
There are many reasons. Some of them are
•To keep the lines equidistant from each other.
•To reduce unwanted vibrations in the track.
•The sleepers have a large surface area compared to the lines; this larger surface area decreases the pressure due to the weight of the train on the track. If only the rails were used without slippers; they being thinner would extent greater pressure over the bed of stone and move deeper in to the ground
Posted by Thakur Hans Raj 3 years, 11 months ago
- 1 answers
Gaurav Seth 3 years, 11 months ago
- Tissue that forms the inner lining of our mouth → squamous epithilium
- Tissue that connects muscle to bone in humans → tendons
- Tissue that transports food in plants → Phloem
- Tissue that stores fat in our body → Adipose tissue
- Connective tissue with a fluid matrix → Blood
- Tissue present in the brain → Nervous tissue
Posted by M Aravind Muthiah M Aravind Muthiah 3 years, 11 months ago
- 0 answers
Posted by Tamanna Pant 3 years, 11 months ago
- 1 answers
Yogita Ingle 3 years, 11 months ago
Fractional distillation is a type of distillation which involves the separation of miscible liquids. The process involves repeated distillations and condensations and the mixture is usually separated into component parts. The separation happens when the mixture is heated at a certain temperature where fractions of the mixture start to vaporize.
Posted by Shruti Laul 3 years, 11 months ago
- 3 answers
Aditya Kumar Jha 3 years, 11 months ago
Suchitra Sen 3 years, 11 months ago
Posted by Neha Jangid ??? 3 years, 11 months ago
- 2 answers
Posted by Surjeet Mohanty 3 years, 11 months ago
- 1 answers
Yogita Ingle 3 years, 11 months ago
| Chromosome | Chromatid |
| Their Function is to carry the genetic material | Their main function is to enable the cells to duplicate |
| A chromosome occurs throughout the cell’s life cycle | A chromatid, on the other hand are created only when the cell pass through mitosis or meiosis stages |
| Chromosomes are not exact copies of each other. One copy of gene comes from each parent | Sister Chromatids are identical copies of each other |
| Chromosomes have centromeres | It is the Sister Chromatids only who have centromeres |
Posted by Vikash K 3 years, 11 months ago
- 1 answers
Posted by Niket Kr Gupta 3 years, 11 months ago
- 2 answers
Yogita Ingle 3 years, 11 months ago
CFCs contain both chlorine and fluorine. CFCs are very stable and do not get degraded by any natural process. In the ozone layer present in the outer region of the atmosphere (25-40 km above sea level), CFCs are dissociated by ultraviolet light to release free chlorine atoms. Free chlorine atoms catalyse the breakdown of ozone molecules (03) into oxygen. This results in degradation of the ozone layer. Thinning of the ozone layer would allow penetration of ultraviolet light into Earth’s atmosphere causing blindness, skin cancer and mutations.
Posted by Moksha Sahu 3 years, 11 months ago
- 2 answers
Yogita Ingle 3 years, 11 months ago
Soil pollution refers to the contamination of soil with anomalous concentrations of toxic substances. It is a serious environmental concern since it harbours many health hazards. For example, exposure to soil containing high concentrations of benzene increases the risk of contracting leukaemia.
Some common causes of soil pollution are listed below,
- Improper disposal of industrial waste: industries are believed to be one of the leading causes of soil pollution due to improper management and disposal of the toxic wastes generated during industrial activities.
- Excessive and inefficient usage of pesticides and fertilizers: the agriculture industry makes extensive use of chemical fertilizers and pesticides for the growth and maintenance of crops. However, excessive and inefficient use of these toxic chemicals can seriously contaminate the soil.
- Petroleum or diesel spills: leaks in fuel transportation pipes can cause fuel spills. These fuels are known to contain toxic hydrocarbons which can cause soil contamination.
Posted by Pragati Upadhyay 3 years, 11 months ago
- 2 answers
K Keerthana Reddy 3 years, 11 months ago
Amrita Pradeep 3 years, 11 months ago
Posted by Prinshu Kumar 3 years, 11 months ago
- 1 answers
Yogita Ingle 3 years, 11 months ago
The branch which deals with the movement of energy from one form to the other and the relation between heat and temperature with energy and work done is called as thermodynamics. In other terms we can define thermodynamics as the science stream that deals with the study of the combined effects of heat and work on the changes of state of matter confined by the laws of thermodynamics. Chemical reactions which releases heat energy associated with it are converted into different usable forms based on the laws of thermodynamics. The fact that energy can only be transformed from one form to the other forms and its use in different industries is on the basis of energy transformation. We are aware that chemical reactions have energy associated with it. The laws of thermodynamics deal with energy changes during a reaction and are not concerned with the rate at which the reaction is proceeding.
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