Answer:
1.31x10¹¹ g/cm³
Explanation:
The mass of the proton is equal to the mass of the neutron, which is 1.67x10⁻²⁴ g, so the mass of the alpha particle is 4*1.67x10⁻²⁴ = 6.68x10⁻²⁴ g.
1 fm = 1.0x10⁻²³ cm, thus the radius of the alpha particle is 2.3x10⁻¹² cm. If the particle is a sphere, the volume of it is:
V = (4/3)*π*r³, where r is the radius, so:
V = (4/3)*π*(2.3x10⁻¹²)³
V = 5.1x10⁻³⁵ cm³
The density of the particle is the how mass exists per unit of volume, so, it's the mass divided by the volume:
d = 6.68x10⁻²⁴/5.1x10⁻³⁵
d = 1.31x10¹¹ g/cm³
Answer: D. Physical change
Explanation:
Phase changes are physical changes.
Answer:
The candle ran out of oxygen
Explanation:
There is a concept known as the fire triangle, the three things present for a fire to start and burn. Heat, Oxygen, Fuel. Take any one of the three away and the fire goes out. Pour water on a fire, and it absorbs the heat, put a jar over it, it removes the oxygen, stop adding wood to a campfire it goes out.
You can determine if the substance is an acid (below 7) or a base (above 7). It also depends on the type of paper that you use, like litmus paper.
Answer:
A = 2-iodo-2,3-dimethylbutane
B = Ethanol
C = Iodoethane (also called ethyl-iodide)
Explanation:
2-Ethoxy-2,3-dimethylbutane reacts with conc. HI to cleave the oxy-functional group.
On one end, ethanol is formed and on the other hand, 2-iodo-2,3-dimethylbutane is formed.
But ethanol reacts further with conc HI to give iodoethane.
Therefore,
A = 2-iodo-2,3-dimethylbutane
B = Ethanol
C = Iodoethane (also called ethyl-iodide)
This is all shown in the attached image.
Hope this Helps!!!
