CBSE_NCERT- 10th : Chapter wise test-Periodic Classification of elements

2 Marks Questions [2 x 5 = 10 ]

1. An element has electronic configuration 2, 8, 3. What is the atomic number of this element? To which (i) group and (ii) period this element belong?

2. State the positions of (i) isotopes of the same element and (ii) hydrogen in the Modern Periodic Table.

3. How does the tendency to gain electrons change as we go down the 16th group of periodic table? Why?

4. Give reasons for the following : (a) Lithium atom is smaller than sodium atom. (b) Chlorine (atomicnumber 17) is more electronegative than sulphur (atomic number 16)

5. (a) State the Modern Periodic Law. (b) Name the element which has twice as many electrons in its second shell as in its first shell. Write its electronic configuration also.

3 Marks Questions [ 3 x 5 = 15 ]

1. An element X belongs to group 17 and third period of the periodic table. (a) Write electronicconfiguration of the element. What is its valency? (b) Predict its nature, whether it is a metal or non-metal. (c) Give the formula of the compound formed when it combines with an element Y having valency three.

2. Three elements A, B and C have atomic number 7, 8 and 9 respectively. (a) What would be their positions in the Modern Periodic Table (Mention group and period both)? (b) Arrange A, B and C in the decreasing order of their size. (c) Which one of the three elements is most reactive and why?

3. (a) The elements of the second period along with their atomic number in parenthesis are given below : B (5), Be (4), O (8), N (7), Li (3), C (6), F (9) (i) Arrange them in the same order as they are in the periodic table. (ii) Which element has the (i) largest (ii) smallest atom? (b) Why does the atomic radius change as we move from left to right in a period?

4. (a) How is the valency of an element determined from its position in the periodic table? (b) Magnesium has atomic number 12. To which (i) group (ii) period of the periodic table does it belong? (c) The valency of all the elements in a group is same. Why?

5. A part of the periodic table has been shown below :

Group →	1	2	13	14	15	16	17	18
Period ↓
1
2	A	C					E	G
3	B			D			F

Answer the following questions on the basis of position of elements in the above table.

(a) Which element is a noble gas? Give reason.

(b) Which element is most electronegative? Give reason.

5 Marks Questions [ 5 x 1 = 5]

1. What are electron affinity and ionization energy? How they are vary in group and periods in modern periodic table? OR, Two elements ‘A’ and ‘B’ belong to group 1 and 2 respectively in the same period. Compare them with respect to :– (a) Number of valence electrons (b) Valency (c) Metallic character (d) Size of atom (e) Formulae of their oxides.

Answer: Read more »

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

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

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

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

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

CBSE ADDA

Search This Blog