Answer:
Force used by fire extinguisher = 60 N
Explanation:
Given:
Mass of skateboard with fire extinguisher = 50 kg
Acceleration of fire extinguisher = 1.2 m/s²
Find:
Force used by fire extinguisher = ?
Computation:
⇒ Force = Mass × Acceleration
⇒ Force used by fire extinguisher = Mass of skateboard with fire extinguisher × Acceleration of fire extinguisher
⇒ Force used by fire extinguisher = 50 kg × 1.2 m/s²
⇒ Force used by fire extinguisher = 60 N
Answer:
The mass, CO2 and CO3 from the limestone sample is discussed below in details.
Explanation:
(A) mass loss of sample of limestone after 20 min
= 0.8437g-0.5979g = 0.2458 g
From the given reaction of limestone, 2 mol of the sample gives 2 moles of CO 2.
Therefore
184.4 g ( molar mass of limestone) gives2× 44 g of carbon dioxide.
1 g of sample gives 88/184.4 g of carbon dioxide
Hence 0.2458 g sample gives
= 88/184.4 × 0.2458 g = 0.117 g carbon dioxide
(B) mole of CO 2 lost = weight/ molar mass
= 0.117 g / 44 g/mol =0.0027 mole
(C). 1 mol of limestone contain 2 mol of carbonate ion
From the reaction we know that carbonate ion of limestone is converted into carbondioxide
Hence lost carbonate ion = 0.2458 g
(D) we know that
1 mol limestone contain 1mol CaCO 3
Hence in sample present CaCO 3
= 1mole / 184.4 g × 0.8437 g= 0.00458 mol CaCO3
Explanation:
1. Thermochemical equation is balance stoichiometric chemical equation written with the phases of the reactants and products in the brackets along with the enthalpy change of the reaction.
The given correct thermochemical reactions are:


2. Phase change affect the value of the enthalpy change of the thermochemical equation. This is because change in phase is accompanied by change in energy. For example:


In both reaction phase of water is changing with change in energy of enthalpy of reaction.
<u>answer</u> 1<u> </u><u>:</u>
Law of conservation of momentum states that
For two or more bodies in an isolated system acting upon each other, their total momentum remains constant unless an external force is applied. Therefore, momentum can neither be created nor destroyed.
<u>answer</u><u> </u><u>2</u><u>:</u><u> </u>
When a substance is provided energy<u> </u>in the form of heat, it's temperature increases. The extent of temperature increase is determined by the heat capacity of the substance. The larger the heat capacity of a substance, the more energy is required to raise its temperature.
When a substance undergoes a FIRST ORDER phase change, its temperature remains constant as long as the phase change remains incomplete. When ice at -10 degrees C is heated, its temperature rises until it reaches 0 degrees C. At that temperature, it starts melting and solid water is converted to liquid water. During this time, all the heat energy provided to the system is USED UP in the process of converting solid to the liquid. Only when all the solid is converted, is the heat used to raise the temperature of the liquid.
This is what results in the flat part of the freezing/melting of condensation/boiling curve. In this flat region, the heat capacity of the substance is infinite. This is the famous "divergence" of the heat capacity during a first order phase transition.
There are certain phase transitions where the heat capacity does not become infinitely large, such as the process of a non-magnetic substance becoming a magnetic substance (when cooled below the so-called Curie temperature).