In a chemical reaction, 12g of carbon reacts completely with 32g of oxygen to form carbon dioxide. If only 40g of carbon dioxide is collected, which of the following is the correct conclusion based on the Law of Conservation of Mass?
Carbon dioxide gas escaped during the reaction, so mass was not fully collected.
By the Law of Conservation of Mass, mass is neither created nor destroyed in a chemical reaction: 12 g of carbon + 32 g of oxygen must together give 44 g of carbon dioxide. Since only 40 g of CO₂ was collected, the remaining 4 g of gas must have escaped during the reaction rather than being lost from existence.
Hence, this is the correct answer.
Which of the following statements are correct in relation to the extraction of metals? The metals which lie high in the reactivity series are extracted by the electrolysis of molten ore.
The metals of medium reactivity series exist as sulphides and carbonates in nature. It is easier to extract a metal from its sulphide in comparison to oxides.
What happens when acid is dissolved in water?
The molecular mass of carbon dioxide is:
Which statement best describes an olfactory indicator?
In electrolytic refining, the impure metal is used as which of the following?
Which of the following 'indicators' is used to test the nature of solutions besides litmus paper?
What is the purpose of enrichment of ore before extraction?
Which of the following statements best explains why dry HCl gas does NOT change the colour of dry litmus paper, but aqueous HCl does?
Which of the following is NOT a property associated with compounds?
Which of the following mixtures is NOT homogeneous?
Which of the following pair is correct?
I. Isotopes – different mass numbers
II. Isobars – different atomic numbers
Which of the following is a zone of a flame?
I. Dark
II. Luminous
III. Non-Luminous
Sphalerite is an ore of:
If formula of sodium salt of an anion X is \(Na_2X\) , then the formula of its aluminium salt would be
Which of the following set contains same number of molecules?
A. 1 gram O 2, 2 grams SO 2
B. 1 gram CO 2, 1 gram N 2O
C. 1 gram O 2, 1 gram O 3