Download App

Periodic Classification of Elements — Science STD 10 — Question

CBSE BoardEnglish MediumSTD 10SciencePeriodic Classification of Elements3 Marks
Question
State the merits of Mendeleev’s classification of elements.
✓

Answer

Merits of Mendeleev’s classification of elements:
  1. Mendeleev’s periodic law predicted the existence of some elements that had not been discovered at that time.
  2. Mendeleev’s periodic table could predict the properties of several elements on the basis of their positions in the periodic table.
  3. It could accommodate noble gases when they were discovered.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "[3 Mark Questions]" from Periodic Classification of Elements→Periodic Classification of Elements — all question types→Science STD 10 question papers→CBSE Board STD 10 question papers→CBSE Board question paper generator→

Similar questions

Given below are some elements of the modern periodic table. Atomic number of the element is given in the parentheses: $A(4), B(9), C(14), D(19), E(20)$
a. Select the element that has one electron in the outermost shell. Also write the electronic configuration of this element.
b. Which two elements amongst these belong to the same group? Give reason for your answer.
c. Which two elements amongst these belong to the same period? Which one of the two has bigger atomic radius?
→
Four elements P, Q, R and S have atomic numbers 12,13,14 and 15 respectively.
Answer the following questions giving reasons:
  1. What is the valency of Q?
  2. Classify these elements as metals and non-metals.
  3. Which of these elements will form the most basic oxide?
→
What will happen if slow moving neutrons are made to strike the atoms of a heavy element ${ }_{92} U ^{235}$ ? What?
→
  1. Name the following:
  1. Thread like non-reproductive structures present in Rhizopus.
  2. 'Blobs' that develop at the tips of the non-reproductive threads in Rhizopus
  1. Explain how these structures protect themselves and what is the function of the structures released from the 'blobs' in Rhizopus.
→
What is meant by dominant genes and recessive genes? Give one example of each.
→
With the help of an example, explain how variation leads to evolution.
→
A carboxylic acid $\text{C}_{2}\text{H}_{4}\text{O}_{2}$ reacts with an alcohol in the presence of $\text{H}_{2}\text{SO}_{4}$ to form a compound ‘X’. The alcohol on oxidation with $\text{KMnO}_{4} $ alkaline followed by acidification gives the same carboxylic acid, $\text{C}_{2}\text{H}_{4}\text{O}_{2}$. Write the name and structure of
  1. Carboxylic acid.
  2. Alcohol.
  3. The compound ‘X’.
→
Explain briefly, how rainwater harvesting is done from open spaces around the buildings in city areas.
→
A white shirt has a yellow stain of curry. When soap is rubbed on this shirt during washing, the yellow stain turns reddish-brown. On rinsing the shirt with plenty of water, the reddish-brown stain turns yellow again.
  1. Name the natural indicator present in curry stain.
  2. Explain the changes in colour of this indicator which take place during washing and rinsing the shirt.
  3. What is the nature of soap (acidic/ basic) as shown by the indicator present in curry stain?
→
What is a rainbow? Draw a labelled diagram to show the formation of a rainbow.
→