Why is it important foe scientists to know how many valence electrons a given element has

1 answer:

3 0

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.

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If we decrease the time it takes for a car to travel over the same distance, this will

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C) increase the speed

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Answer:

Explanation:

i = Imax sin2πft

given i = 180 , Imax = 200 , f = 50 , t = ?

Put the give values in the equation above

180 = 200 sin 2πft

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sin2π x 50t = .9

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360 x 50 t = 360n + 64

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Thank you for posting your question here at brainly. I hope the answer will help you. Feel free to ask more questions here.

Have Bobby as a horizontal force pushing towards/against the tv.
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Have the force of fric±on between the Foor and the tv

Maybe another force could be bobby's feet pushing from the Foor and his weight (from gravity) bearingdown on his feet. If he didn't weigh more then the tv then he wouldn't be able to put enough pressureon the Foor to create the gripping fric±on force necessary to push the tv

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Let’s determine the initial momentum of each car.
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This is approximately 28,541. To determine the x component, we need to determine the angle of the final momentum. Use the following equation.

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θ = tan^-1 (499/510)

The angle is approximately 43.85˚ counter clockwise from the negative x axis. To determine the x component, multiply the final momentum by the cosine of the angle.

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Answer:

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