Advertisements
Advertisements
प्रश्न
When magnesium is burnt in air, there is an increase in mass after the reaction.
Advertisements
उत्तर
When magnesium ribbon is burnt in air, a white solid, magnesium oxide, is formed. The mass of magnesium oxide is more than the mass of magnesium. This is because the mass of oxygen used is not taken into account. If that is taken into account, the total mass of the reactants and products is found to be nearly equal.
\[\ce{\underset{magnesium}{2Mg} + \underset{air}{O2} -> \underset{magnesium oxide}{2MgO}}\]
APPEARS IN
संबंधित प्रश्न
Hydrogen and oxygen combine in the ratio of 1:8 by mass to form water. What mass of oxygen gas would be required to react completely with 3 g of hydrogen gas?
State the law of conversation of mass.
What do you observe when, barium chloride solution is mixed with sodium sulphate solution ?
What is mass ?
Fill in the blank:
Matter is anything that has............. and occupies .............
Name the scientist who gave law of conservation of mass.
Name the law of chemical combination which was given by Lavoisier.
Name the law of chemical combination which was given by Proust.
State the law of conservation of mass. Give one example to illustrate this law.
Copper sulphate reacts with sodium hydroxide to form a blue precipitate of copper hydroxide and sodium
sulphate. In an experiment, 15.95 g of copper sulphate reacted with 8.0 g of sodium hydroxide to form
9.75 g of copper hydroxide and 14.2 g of sodium sulphate. Which law of chemical combination is illustrated by this data ? Give reason for your choice.
An ionic compound will be formed by the combination of one of the following pairs of elements. This pair of elements is :
State the ‘law of conservation of mass’.
Select the correct answer from A, B, C, D & E for the statement given below:
The process of change of a liquid into vapour, [gas] on heating.
Complete the statement by filling the blank with the correct word given below.
The law of conservation of mass is strictly valid if mass and _________ are considered together.
Match the following.
| Law of conservation of mass | Sir William Crookes |
| Law of constant proportion | James Chadwick |
| Cathode rays | Joseph Proust |
| Anode rays | Lavoisier |
| Neutrons | Goldstein |
Why does a light paddle wheel placed in the path of cathode rays begin to rotate, when cathode rays fall on it?
Name the four laws of chemical combinations.
