Because the number of valence electrons of an element determines the properties and in particular the reactivity of that element.
In fact, elements of the first group (i.e. only one valence electron) have high reactivity, because they can easily give away their valence electron to atoms of other elements forming bonds. On the contrary, elements of the 8th group (noble gases) have their outermost shell completely filled with electrons, so they do not have valence electrons, and they have little or no reactivity at all.
Answer: 3.75 joules
Explanation:
Given that:
Mass of acorn = 0.300 kilograms
velocity = 5.oo m/s
Kinetic energy = ?
Since, kinetic energy is the energy possessed by a moving object, its value depends on the mass M and velocity V of the acorn.
Thus, Kinetic energy = 1/2 x mv^2
= 1/2 x 0.300kg x (5.00m/s)^2
= 0.5 x 0.3kg x (5.00m/s)^2
= 0.15 x (5.00m/s)^2
= 3.75 joules
Thus, the kinetic energy of the falling acorn is 3.75 joules
Radio waves, infrared rays, visible light, ultraviolet rays, X-rays, and gamma rays are all types of electromagnetic radiation. Radio waves have the longest wavelength, and gamma rays have the shortest wavelength.
Answer:
Approximate height of the building is 23213 meters.
Explanation:
Let the height of the building be represented by h.
0.02 radians = 0.02 × 
= 0.02 x (180/
)
0.02 radians = 1.146°
10.5 km = 10500 m
Applying the trigonometric function, we have;
Tan θ = 
So that,
Tan 1.146° = 
⇒ h = Tan 1.146° x 10500
= 2.21074 x 10500
= 23212.77
h = 23213 m
The approximate height of the building is 23213 m.
