Advertisements
Advertisements
प्रश्न
While performing the experiment with raisins to determine the percentage of water absorbed by them, a student made following measurements:
Mass of water in the beaker = 40 g
Mass of raisins before soaking = 5 g
Mass of raisins after soaking for 2 hours = 8 g
Mass of water left in the beaker after the experiment = 35 g
The percentage of water absorbed by raisins is:
पर्याय
`(40g-35g)/(35g)xx100`
`(40g-35g)/(40g)xx100`
`(8g-5g)/(8g)xx100`
`(8g-5g)/(5g)xx100`
Advertisements
उत्तर
Not in Current Syllabus
The percentage of water absorbed by raisins is calculated by using the formula
`(W_2-W_1)/(W_1)xx100`
where, W2 is the weight of wet resin and W1 is the weight of dry resin.
The Correct Answer is D
संबंधित प्रश्न
Correct and balance the following equation:
\[\ce{Ca + H2O -> CaOH + H}\]
When metal X is treated with a dilute acid Y, then a gas Z is evolved which burns readily by making a little explosion.
- Name any two metals which can behave like metal X.
- Name any two acids which can behave like acid Y.
- Name the gas Z.
- Is the gas Z lighter than or heavier than air?
- Is the reaction between metal X and dilute acid Y exothermic or endothermic?
- By taking a specific example of metal X and dilute acid Y, write a balanced chemical equation for the reaction which takes place. Also indicate physical states of all the reactants and products.
Write your observations and name the product when
Iron nails are added to an aqueous solution of copper sulphate.
Write word equation for the following skeletal equation:
\[\ce{KNO3 -> KNO2 + O2}\]
Write your observation and name the product when zinc reacts with dilute hydrochloric acid.
Name the following:
The gas evolved when a dilute acid is added to chalk [limestone].
\[\ce{2KClO3->[MnO2] 2KCl + 3O2[g] - is a balanced equation.}\]
Give a reason why the above equation is balanced.
Balance the following simple equation:
KHCO3 → K2CO3 + H2O + CO2
Give a balanced equation by the partial equation method, [steps are given below].
Oxidation of Lead [II] Sulphide by Ozone
- Ozone first decomposes to give molecular oxygen & nascent oxygen.
- Nascent oxygen then oxidises lead [II] sulphide to lead [II] sulphate.
Balance the given chemical reaction as per the instructions below.
\[\ce{NaOH + H2SO4 -> Na2SO4 + H2O}\]
Write the number of atoms of various elements in the reactants and products.
