B. -2
C. +2
D. +1
When a potassium atom loses one electron, it forms a potassium ion. Since electrons carry a negative charge, losing one electron results in an overall positive charge for the ion. Therefore the correct answer is (D).
A potassium atom normally has 19 protons and 19 electrons. The number of protons and electrons is equal, so the atom is electrically neutral overall.
However, when a potassium atom loses one electron, it means that it now has 19 protons and only 18 electrons. Since protons are positively charged and electrons are negatively charged, losing one negatively charged electron leaves the atom with a net positive charge.
Since there is one more positive charge than a negative charge, the potassium ion has a positive charge of +1. This means the potassium ion has one more positive charge than it has negative charges, making it a cation with a +1 electrical charge.
In summary, when a potassium atom loses one electron, it becomes a potassium ion with a positive charge of +1. Therefore the correct answer is (D).
To know more about the potassium atom:
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Answer:
Breeder reactors are different from conventional nuclear reactors because they produce more fuel than they consume when producing energy and can re-use the plutonium they produce to fuel the reactor.
Explanation:
Nuclear reactors use uranium as a source of fuel to generate the required energy.These reactors produce less fissionable matter than they consume.For example, the amount of plutonium produced in nuclear rectors is less than that produced in Breeder reactors.In Breeder reactors, the plutonium produced can be separated and collected to be reused as fuel in the reactor.Additionally, breeder reactors use a coolant such as liquid sodium equipping the neutrons with high energy thus increasing the chances of the neutrons to be captured by uranium isotopes and be converted to plutonium.
It increases their attention span.
It increases their learning ability.
It increases their chance of obesity.
Answer:
It increases asthma rates
Explanation:
The speed of the car is 75 km/h
These are the formulas that we have to remember before solving the problem.
Speed is the rate of change of distance.
v = speed ( m/s )
d = distance ( m )
t = time ( s )
Acceleration is the rate of change of velocity.
a = acceleration ( m/s² )
Δv = change in speed ( m/s )
t = time ( s )
Let us now tackle the problem!
Given:
distance = d = 150 km
time taken = t = 7200 s = 2 hours
Unknown:
velocity = v = ?
Solution:
The acceleration of the car is 0 m/s² because it travels with constant speed.
We could also plot the distance vs time graph as shown in the attachment.
Grade: Middle School
Subject: Physics
Chapter: Kinematics
Keywords: indycar top speed of a fastest police car has ever gone
The car's speed is 75 km/hour, as determined by dividing the total distance travelled (150 km) by the total time taken (2 hours).
To answer this question, we use the
formula for speed
, which is distance traveled divided by the time taken. Here, the distance travelled by the car is 150 km and the time taken is 7200 s (which is equal to 2 hours). Therefore, the speed will be 150 km divided by 2 hours, resulting in a speed of
75 km/hour
, stated to the correct number of significant figures.
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As per the question, the object is thrown in vertically upward direction.
The initial velocity of the ball [u] = 9 m/s.
We are asked to calculate the velocity of the ball after 2 second.
When the ball goes up, the only force that acts on the ball is the force of gravity.
Hence the acceleration of the ball is nothing else than acceleration due to gravity i.e g and it is downward in direction.
Here, it will be considered negative as it is downward in direction .
From equation of kinematics we know that-
v = u +at [Here v is the final velocity and a is the acceleration.
= 9 +[-9.8]×2 m/s
= 9-19.6
= -10.6 m/s
Here the negative sign indicates that the ball is falling downward. It is coming back after reaching its maximum height.
Here the total time of flight of the ball is-
If the ball is thrown from certain height from the ground, then the velocity of the ball will be the calculated value.
If the ball is thrown from the ground, obviously the ball will heat the ground after 1.8367 seconds later.So the velocity of the ball will be zero after 2 seconds.