We all know that we need energy to stay alive. We get this energy from the food we eat. During digestion, food is broken down into simpler substances. For example, rice, potatoes and bread contain carbohydrates. These carbohydrates are broken down to form glucose.This glucose combines with oxygen in the cells of our body and …
Do you know that respiration is an exothermic process ? Read More »
A solution of slaked lime produced by the reaction is used for whitewashing walls. Calcium hydroxide reacts slowly with the carbon dioxide in air to form a thin layer of calcium carbonate on the walls. Calcium carbonate is formed after two to three days of whitewashing and gives a shiny finish to the walls. It …
Combination Reaction Definition “Two or more reactants (elements or compounds) combine and formed a single product is known as a combination reaction.“ eg Calcium oxide reacts vigorously with water to produce slaked lime (calcium hydroxide) releasing a large amount of heat. CaO (s) + H2O (l) → Ca(OH)2 (aq) + Heat (Quick lime) (Slaked lime) …
when a magnesium ribbon is burnt in oxygen, it gets converted to magnesium oxide. This description of a chemical reaction in a sentence form is quite long. It can be written in a shorter form. The simplest way to do this is to write it in the form of a word-equation.The word-equation for the above …
WHAT IS CHEMICAL EQUATION ? HOW TO WRITE CHEMICAL EQUATION ? Read More »
Chemical equationIt is the representation of a chemical reaction in the form of symbols and formulae of reactants and product(s) involved in a chemical reaction eg 2 H2(g) + O2(g) → 2 H2O(ℓ) Chemical Reaction Any chemical change in matter or a substance which involves formation of one or more new substances eg Hydrogen and …
Differentiate Chemical reaction and Chemical equation Read More »
Solution:Mass of luggage, m = 15 kg anddisplacement, s = 1.5 m. Work done, W = F × s = mg × s= 15 kg × 10 m s-2 × 1.5 m= 225 kg m s-2 m= 225 N m = 225 JWork done is 225 J.
Solution:Mass of the car, m =1500 kg, initial velocity of car, u = 30 km h–1= 30 × 1000m / 60 × 60s= 25/3 m s–1.Similarly, the final velocity of the car,v = 60 km h–1 = 50/3 m s–1.Therefore, the initial kinetic energy of the car,K Ei = 1/2 m u2 = 1/2× 1500 …
Solution:Mass of the object, m = 15 kg, velocityof the object, v = 4 m s–1, E = 1/2 m v2 k . E = 1 / 2 × 15 kg × 4 m s–1 × 4 m s–1= 120 JThe kinetic energy of the object is 120 J.
Solution:Mass of the object, m = 10 kg,displacement (height), h = 6 m, andacceleration due to gravity, g = 9.8 m s–2Potential energy = m g h= 10 kg × 9.8 m s–2 × 6 m= 588 J.The potential energy is 588 J.
