All categories

3 years ago

Where do you find elements grouped that have the most similar physical and chemical properties?

1 answer:

7 0

The chemical properties depend on the number of valence shell electrons since these electrons participate in chemical bond formation with other elements. The elements are arranged in the periodic table in such a way that the elements having same number of electrons in the valence shell are grouped together.

Therefore the chemical properties of the elements present in the same group are similar. As for example the halogens (Group VII) made up of fluorine, chlorine, bromine, iodine and astatine. In fact since they all seven electrons in the valence shell they are therefore called halogens. All halogens exhibit similar chemical properties. It is true for all other groups.

The physical properties like melting point , boiling point partially depend on the valence shell and it also depends on the type of interactions between the atoms of the element. Thus to some extent it shows similarity along a group.

You might be interested in

A .025 kg bullet is moving at 350 m/s when it hits and then passes through a 7 kg block of wood. After the bullet passes through

slamgirl [31]

Answer:

The final velocity of the wooden block is equal to $1.035 m/s$

Explanation:

Given that mass of bullet = $m_{b} = 0.025kg$

Mass of wood = $m_{w} = 7kg$

Initial velocity of bullet = $u_{b} = 350m/s$

Final velocity of bullet = $v_{b} = 60m/s$

Initial velocity of wood = o

Final velocity of wood = $v_{w]$

Here momentum is conserved so initial momentum = final momentum

$m_{b}u_{b} = m_{b} v_{b} + m_{w}v_{w}$ .

Upon substituting these values in above equation , we get

$v_{w} = 1.035m/s$ .

7 0

3 years ago

• How much work is<br>required to lift a 2kg<br>object 2m high?<br>

pychu [463]

Answer You need to consider that the gravity on earth is 9.8 m/s/s. This means any object you let go on the earths surface will gain 9.8 m/s of speed every second. You need to apply a force on the object in the opposite direction to avoid this acceleration. If you are pushing something up at a constant speed, you are just resisting earths acceleration. The more massive and object is, the greater force is needed to accelerate it. The equation is Force = mass*acceleration. So for a 2kg object in a 9.8 m/s/s gravity you need 2kg*9.8m/s/s = 19.6 Newtons to counteract gravity. Work or energy = force * distance. So to push with 19.6 N over a distance of 2 meters = 19.6 N*2 m = 39.2 Joules of energy. There is an equation that puts together those two equations I just used and it is E = mgh

The amount of Energy to lift an object is (mass) * (acceleration due to gravity) * (height)

:Hence, the Work done to life the mass of 2 kg to a height of 10 m is 196 J. Hope it helps❤️❤️❤️

Explanation:

7 0

3 years ago

8. A sprinter on a school track team is running north at a velocity of 6.0 m/s. After 5.0 s, she

Marysya12 [62]

Answer:

acc. = 4-(-6) /5= 10/5=2 m/s^2

6 0

2 years ago

A ceiling fan has three blades. The moment of inertia of a blade is 0.2kgm^2. The net torque exerted on fan blades is 8Nm. Find

olchik [2.2K]

Answer:

(A) the angular acceleration of the blades is 13.33 m/s.

Explanation:

Given;

moment of inertia of a blade, I = 0.2 kgm²

net torque exerted on fan blades, ∑τ = 8Nm

Torque is given as product of moment of inertia and angular acceleration;

τ = Iα

where;

α is the angular acceleration

Since there are three blades of the ceiling fan, the net torque is given as;

∑τ = (3I)α

∑τ = 3Iα

α = ∑τ / 3I

α = (8) / (3 x 0.2)

α = 13.33 m/s

Therefore, the angular acceleration of the blades is 13.33 m/s.

8 0

2 years ago

An automobile with an initial speed of 4.92 m/s accelerates uniformly at the rate of 3.2 m/s2 . Find the final speed of the car

Rudik [331]

Answer:19.32 m/s

Explanation:

Given

initial speed of car(u)=4.92 m/s

acceleration(a)= $3.2 m/s^2$

Speed of car after 4.5 s

using equation of motion

v=u+at

$v=4.92+3.2\times 4.5=4.92+14.4$

v=19.32 m/s

Displacement of the car after 4.5 s

$v^2-u^2=2as$

$19.32^2-4.92^2=2\times 3.2\times s$

$349.05=2\times 3.2\times s$

s=54.54 m

4 0

2 years ago