Skip to main content

TET/CTET Science study notes for paper-II

Properties of Metals

Metals are solids at room temperature with the exception of mercury and gallium, which are liquids at room temperature. Gallium and Caesium melt below 30c . So if room temperature is around 30c, they may also be in liquid state

Metals are hard but not brittle, except zinc at room temperature.

Metals, in their pure state, have a shining surface. This property is called metallic luster e.g., gold, silver and copper


Metals can be beaten into thin sheets known as foils. This property is called malleability. Gold and silver are the most malleable metals.

The ability of metals to be drawn into thin wires (except sodium, potassium, calcium, lead etc.)is called ductility. Gold is the most ductile metal. It is because of their malleability and ductility that metals can be given different shapes according to our needs like for making cooking vessels or making jewellery.

Metals are generally hard except sodium and potassium, which are soft and can be cut with a knife.

When metals strike a hard surface produce a sound and are said to be sonorous like iron or aluminum

Metals have high melting points but gallium and caesium have very low melting points.

Metals have 1 to 3 electrons in the outermost shell of their atoms. The greater the number of shells and lesser the number of valence electrons, the greater is the reactivity of the metal.

Metals are good conductors as they have free mobile electrons. Silver and copper are the two best conductors of heat and electricity. Lead is the poorest conductor of heat. Bismuth, mercury and iron are also poor conductors.

Metals have high density and are very heavy except sodium, potassium, calcium etc. Iridium and osmium have the highest densities where as lithium has the lowest density.

Metals have high melting and boiling point except mercury, cesium, gallium, tin, lead. Tungsten has the highest melting point where as silver has low boiling point. Sodium and potassium have low melting points.

Metals always ionize by losing electrons and become positively charged ion or Cation
 Na - 1e- à Na+

Metals are always deposited at the cathode during electrolysis.

Metals lose electrons and hence get oxidized. Hence They are reducing agents.

Metals generally form basic oxides, some of which are also amphoteric, such as aluminium oxide, zinc oxide, lead oxide etc.

Metals usually do not form hydrides by reacting with hydrogen except those of sodium, potassium and calcium.

Metal react with chlorine and produce chlorides, which are electrovalent.

Metals on reaction with dilute acids they give respective salt and hydrogen.


Properties of Non-metals
Non-metals exist in two of the three states of matter at room temperature: gases (oxygen) and solids (carbon). These have no metallic lustre, and do not reflect light. 

Non-metals are not lustrous, except iodine and diamond which is the most lustrous of all the substances

Non-metals are usually not hard exception is diamond which is the hardest substance.

Non-metals are very brittle, and cannot be rolled into wires or pounded into sheets.

Non-metals are poor conductors of heat and electricity except for carbon in the form of graphite and the gas carbon

Non-metals have a tendency to gain or share electrons with other atoms. They are electronegative in character. By gaining electron form anions

Non-metals generally form acidic or neutral oxides with oxygen.

Non-metals have 4, 5, 6 or 7 electrons in the valence shell. If it has 8 electrons, it is called a noble gas. Lesser the number of shells and greater the number of valence electrons, greater is the reactivity of the non-metal.

Non-metals gain electrons to form anions and hence get reduced and act as a oxidizing agents.

Non-metal gain or share electron so exhibit both electrovalency or covalency.

Non-metals are always deposited at the anode during electrolysis.

Non-metals generally form acidic oxides when react with oxygen. Some oxides are neutral, such as nitrous oxide, nitric oxide, carbon monoxide water etc

Non-metals produce chlorides, which are covalent when, react with chlorine

Non-metals  form hydrides when react with hydrogen , e.g. NH3, PH3, HCl,  HBr, HI, H2S, H2O etc.

Comments

CBSE ADDA :By Jsunil Sir : Your Ultimate Destination for CBSE Exam Preparation and Academic Insights

Class 10 Chapter 02 Acid Bases and Salts NCERT Activity Explanation

NCERT Activity Chapter 02 Acid Bases and Salt Class 10 Chemistry Activity 2.1 Indicator Acid Base Red litmus No Change Blue Blue Litmus Red No change Phenolphthalein Colourless Pink Methyl Orange Pink   Yellow Indictors are substance which change colour in acidic or basic media. Activity 2.2 There are some substances whose odour changes in in acidic or basic media. These are called olfactory indicators. Like onion vanilla, onion and clove. These changes smell in basic solution. Activity 2.3 Take about 5 mL of dilute sulphuric acid in a test tube and add few pieces of zinc granules to it. => You will observe bubbles of hydrogen gas on the surface of zinc granules. Zn + H2SO4 --> ZnSO4 + H2 => Pass the Hydrogen gas through the soap solution. Bubbles formed in the soap solution as Hydrogen gas it does not get dissolved in it

CBSE I NCERT 10th Numerical Problem solved Reflection and reflection of light

Q. 1. A concave mirror of focal length 20cm is placed 50 cm from a wall. How far from the wall an object be placed to form its real image on the wall?  Solution: V= -50 cm F= -20cm From mirror formula 1/u = 1/f – 1/v = -1/20+ 1/50 = - 3/100  U = - 33.3 cm Therefore, the distance of the object from the wall x =  50 – u X = 50 – 33.3 = 16.7 cm. Q.2. An object is placed at a distance of 40cm from a concave mirror of focal length 15cm. If the object is displaced through a distance of 20 cm towards the mirror, By how much distance is the image displaced? Answer: Here f = - 15 cm, u = - 40 cm Now 1/f = 1/u + 1/v Then 1/v = 1/f – 1/u Or V= uf/u-f =( - 40 x -15)/25 = -24 cm Then object is displaced towards the mirror let u1 be the distance object from the Mirror in its new position. Then u1 = -(40-20) = -20cm If the image is formed at a distance u1 from the mirror then v1 = u1f/u1-f = -20X-15/-20+15 = -60 cm. = - 20 x-15/-20+15 = -60 cm. Therefor

Class 10 Metal and Non MetalsChapter 03 NCERT Activity Solutions

X Class 10 NCERT Activity Explanation Class 10 Metals and Non Metals Activity 3.1 Page No. 37 Take samples of iron, copper, aluminium and magnesium. Note the appearance of each sample. They have a shining surface. Clean the surface of each sample by rubbing them with sand paper and note their appearance again. They become more shiny. => Freshly cut Metal have shiny surface Activity 3.2 Page No. 37 Take small pieces of iron, copper, aluminium, and magnesium. Try to cut these metals with a sharp knife and note your observations. They are very hard to cut. Hold a piece of sodium metal with a pair of tongs and try to cut it with a knife. Sodium can be cut easily with knife. Hence K and Na are soft metal cut with knife Activity 3.3 Page No. 38 Take pieces of iron, zinc, lead and copper try to strike it four or five times with a hammer. These metals are beaten into thin sheet on hammering. This property of metal is called malleability and metals are called malleable. Activity 3.4 Page

Living science ratna sagar class 6 solutions

Ratna sagar living science 6 answers by jsunil. Class6 Living science solution Term-1 Living Science Solution chapter-1 Source of food Download File Living Science Solution chapter-2 Component of food Download File Living Science Solution chapter-3 Fibre to fabric Download File Living Science Sol ch-4 Sorting of material into group Download File Living Science Soln ch-5 Separation of substance Download File Living Science Solution chapter-6 Change around Us Download File Living Science Solution ch-7 Living and Non Living Download File Living Science Solution ch-8 Getting to Know Plants Download File Living Science Sol ch-9 The Body and Its movements Download File Visit given link for full answer Class6 Living science solution Term-II

Electricity numerical for class 10 CBSE Trend Setter 50 Problems

1. The current passing through a room heater has been halved. What will happen to the heat produced by it? 2. An electric iron of resistance 20 ohm draws a current of 5 amperes. Calculate the heat produced in 30 seconds. 3. An electric heater of resistance 8 ohm takes a current of 15 A from the mains supply line. Calculate the rate at which heat is developed in the heater. 4. A resistance of 40 ohms and one of 60 ohms are arranged in series across 220 volt supply. Find the heat in joules produced by this combination in half a minute. 5. A resistance of 25 ohm is connected to a 12 V battery. Calculate the heat energy in joules generated per minute. 6. 100 joules of heat is produced per second in a 4 ohm resistor. What is the potential difference across the resistor? 7. An electric iron is connected to the mains power supply of 220 V. When the electric iron is adjusted at minimum heating’ it consumes a power of 360 W but at ‘maximum heating’ it takes a power of 840 W. Ca