Answer:
Option (C) from a vacuum to air
Explanation:
Speed of light in any media depends on the refractive index(n) of the medium in which light is travelling.The medium having least refractive index have the fastest speed of the light.As the refractive index of the vacuum is less(1.0000) than that of the air(1.0003), so the speed of light will slows down while moving from vacuum to air.The refractive index 'n' is the ratio between speed of light in vacuum(c) to the speed at which the light is travelling i.e v, (n = c / v).
Answer:
A. 3.36g of Na.
B. 14.62g of Ba3(PO4)2.
Explanation:
We'll begin by writing the balanced equation for the reaction. This is given below:
3Ba + 2Na3PO4 → 6Na + Ba3(PO4)2
Next, we shall determine the mass of Ba that reacted and the mass of Na and Ba3(PO4)2 produced from the equation.
This is illustrated below:
Molar Mass of Ba = 137g/mol
Mass of Ba from the balanced equation = 3 x 137 = 411g
Molar mass of Na = 23g/mol
Mass of Na from the balanced equation = 6 x 23 = 138g
Molar mass of Ba3(PO4)2 = (3 x 137) + 2[31 + (4x16)] = 411 + 2[31 + 64] = 601g/mol
Mass of Ba3(PO4)2 from the balanced equation = 1 x 601 = 601g
Summary:
From the balanced equation above,
411g of Ba reacted to produce 138g of Na and 601g of Ba3(PO4)2.
A. Determination of the mass of Na produced by reacting 10g of Ba.
From the balanced equation above,
411g of Ba reacted to produce 138g of Na.
Therefore, 10g of Ba will react to produce = (10 x 138)/411 = 3.36g of Na.
Therefore, 3.36g of Na is produced.
B. Determination of the mass of Ba3(PO4)2 produced by reacting 10g of Ba.
From the balanced equation above,
411g of Ba reacted to produce 601g of Ba3(PO4)2.
Therefore, 10g of Ba will react to produce = (10 x 601)/411 = 14.62g of Ba3(PO4)2.
Therefore, 14.62g of Ba3(PO4)2 is produced.
B.two gases
C.a solid and a liquid
D.a liquid and a gas
The correct answer is b. two gases
The explanation:
-Mixtures can be either homogeneous or heterogeneous. A homogeneous mixture is a type of mixture in which the composition is uniform and every part of the solution has the same properties.\
- Examples of homogeneous mixtures include alloys and alcohol in water. A heterogeneous mixture is a type of mixture in which the components can be seen.
-One example of a mixture is air. Air is a homogeneous mixture of the gaseous substances nitrogen, oxygen, and smaller amounts of other substances.
Answer: B.two gases
Explanation: Homogeneous mixtures are mixtures in which dispersed phase is uniformly distributed throughout the dispersion medium and there is no physical boundary between the dispersed phase and dispersion medium.
Heterogeneous mixtures are mixtures in which dispersed phase is not uniformly distributed throughout the dispersion medium and there is a distinct physical boundary between the dispersed phase and dispersion medium.
a) Two liquids may or may not be completely miscible thus may form a homogeneous (milk and water) or a heterogeneous mixture (oil and water).
b) Two gases always form a homogeneous mixture as there is large vacant spaces present between the molecules.
c) A solid and a liquid may or may not be completely miscible thus may form a homogeneous (salt and water) or a heterogeneous mixture ( sand and water).
d) A liquid and a gas may or may not be completely miscible thus may form a homogeneous (river water) or a heterogeneous mixture (perfume spray).
How is salicylic acid obtained?
Explanation:
A catalyst lowers the activation energy of a reaction allowing them to proceed faster than they would naturally. Activation energy is the free energy that is required to be input in the reactant side to activate them to the transition state after which the reaction proceeds spontaneously to products.
An example of a catalyst is platinum, that is put in the exhaust of cars, to help convert carbon monoxide to carbon dioxide before it is emitted into the air.
Answer: they lower these activation required for the reactions to take place.
Explanation: