All categories

3 years ago

HELP ASAP!!! What was Johann Dobereiner’s contribution to the development of the periodic table?

Physics

2 answers:

Nataly_w [17]3 years ago

8 0

He identified triads of elements that had similar properties

galina1969 [7]3 years ago

6 0

Answer;

3) He identified triads of elements that had similar properties.

Explanation;

Each of Dobereiner's triads was a group of three elements. The appearance and reactions of the elements in a triad were similar to each other.

Dobereiner discovered that the relative atomic mass of the middle element in each triad was close to the average of the relative atomic masses of the other two elements. This gave other scientists a clue that relative atomic masses were important when arranging the elements.

You might be interested in

If a bicycle travels 1200m, and it takes 300seconds, what is its speed in m/s.

ch4aika [34]

Answer: 4

Explanation: speed= distance/time

7 0

3 years ago

You observe two cars traveling in the same direction on a long, straight section of Highway 5. The red car is moving at a consta

Romashka-Z-Leto [24]

Answer:

a) 3.66 s

b) 124.4 m

c) 3.12s

Explanation:

Given that

Speed of the Red Car, v₁ = 34 m/s

Speed of the Blue Car, v₂ = 28 m/s

Distance between the two cars, d = 22 m

The difference between the speed of the cars is: 34 - 28 = 6 m/s

From this, we can deduce that the red car will be catching up to the blue car at a speed of 6 m/s.

If we divide the distance by the difference in speed. This becomes

d/v = 22/6 = 3.66 s. Which means, It takes 3.66 seconds for the red car to meet up with the blue car.

From the previous part, we were able to confirm that it took 3.66 seconds for the red car to meet up the blue car. Also, the speed with which it were traveling was travelling at, was constant, so we only need to multiply it by the time from (1) to get the distance.

v = d * t = 34 * 3.66 = 124.4

Therefore the red car travels at 124.4 m before catching up to the blue car.

If the red car starts to accelerate the moment we see it, the time it will take, to get to the blue car will be less than what we had gotten. We can find this using one of the equations of motion.

S = ut + ½gt², where

S = 22

u = 6

t = ?

g = 2/3

22 = 6t + 1/3t²

By using the quadratic formula, we find out the two answers listed below

t1 = 3.12 s

t2 = - 21.12 s

We all know that negative time is not possible, so the answer is t1. At 3.12 seconds

8 0

3 years ago

How long would i t take to walk around the eath nonstop?

zaharov [31]

Divide (25,000) by (the number of miles you can walk in 1 hour).
The answer you get is the number of hours it would take you to walk around the Earth once, IF you were able to walk on water too.

4 0

3 years ago

Collar P slides outward at a constant relative speed along rod AB, which rotates counterclockwise with a constant angular veloci

diamong [38]

Answer:

a= 23.65 ft/s²

Explanation:

given

r= 14.34m

ω=3.65rad/s

Ф=Ф₀ + ωt

t = Ф - Ф₀/ω

= (98-0)× $\frac{\pi}{180}$ /3.65

98°= 1.71042 rad

1.7104/3.65

t= 0.47 s

r₁(not given)

assuming r₁ =20 in

r₁ = r₀ + ut(uniform motion)

u = r₁ - r₀/t

r₀ = 14.34 in= 1.195 ft

r₁ = 20 in = 1.67 ft

= (1.667 - 1.195)/0.47

0.472/0.47

u= 1.00ft/s

acceleration at collar p

a=rω²

= 1.67 × 3.65²

a = 22.25ft/s²

acceleration of collar p related to the rod = 0

coriolis acceleration = 2ωu

= 2× 3.65×1 = 7.3 ft/s²

acceleration of collar p

= 22.5j + 0 + 7.3i

√(22.5² + 7.3²)

the magnitude of the acceleration of the collar P just as it reaches B in ft/s²

a= 23.65 ft/s²

4 0

3 years ago

When a person steps forward out of a small boat onto a dock, the boat recoils backward in the water. why does this occur??

bixtya [17]

Here is the correct answer of the given question above. When a person steps forward out of a small boat onto a dock, the boat recoils backward in the water and this occurs because the total momentum of the system is conserved. Hope this helps.

4 0

3 years ago

Read 2 more answers