Advertisements
Advertisements
Question
When magnesium is burnt in air, there is an increase in mass after the reaction.
Advertisements
Solution
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
RELATED QUESTIONS
In a reaction, 5.3 g of sodium carbonate reacted with 6 g of acetic acid. The products were 2.2 g of carbon dioxide, 0.9 g water and 8.2 g of sodium acetate. Show that these observations are in agreement with the law of conservation of mass.
Sodium carbonate + acetic acid → sodium acetate + carbon dioxide + water
Which postulate of Dalton’s atomic theory is the result of the law of conservation of mass?
State the law of conversation of mass.
What is mass ?
If an object weighs 6 kg on earth. What will be its weight on moon ?
If an object is taken to the moon from the earth what will be its mass ?
Give reason for the following.
Electricity is not considered matter.
Fill in the blank:
Matter is anything that has............. and occupies .............
Name the law of chemical combination which was given by Lavoisier.
Name the law of chemical combination which was given by Proust.
‘If 100 grams of calcium carbonate (whether in the form of marble or chalk) are decomposed completely, then 56 grams of calcium oxide and 44 grams of carbon dioxide are obtained’. Which law of chemical combination is illustrated by this statement ?
State the law of conservation of mass. Give one example to illustrate this law.
Which postulate of Dalton's atomic theory can explain the law of conservation of mass ?
An ionic compound will be formed by the combination of one of the following pairs of elements. This pair of elements is :
Complete the statement given below by filling in the blanks with the correct words.
Atoms contain ________ with positively charged ________.
Select the correct answer from A, B, C, D & E for the statement given below:
In Landolt’s experiment – the form in which the chemical energy stored up in the reactants __________ is released.
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.
