Answer:
Newton's Cradle is a neat way to demonstrate the principle of the CONSERVATION OF MOMENTUM.
What happens here is when the ball on one end of the cradle is swung and it hits the other balls that are motionless, or stationary, the momentum of the swinging ball is transferred to the next ball upon impact.
Momentum is not lost in this action, what happens when it hits the next ball, the momentum is transferred to the next one, and then the next, and the the next, till it reaches the last ball on the other end. Since nothing is next to the last ball, it pushes the ball upwards, which will swing down and repeat the process going the other way.
This also demonstrates the CONSERVATION OF ENERGY. As you will see, the energy continues to move through the other balls, passing it from one ball to the other, which keeps this constantly moving.
Answer: D. Sends small electrical impulses to the heart, causing it to beat more
Explanation: A pacemaker is implanted in the chest and helps to treat abnormal heart rhythms especially those causing your heart to skip beats or beat too slow.
Answer:
HCl
Explanation:
Given data:
Mass of Zn = 50 g
Mass of HCl = 50 g
Limiting reactant = ?
Solution:
Chemical equation:
Zn + 2HCl → ZnCl₂ + H₂
Number of moles of Zn:
Number of moles = mass / molar mass
Number of moles = 50 g/ 65.38 g/mol
Number of moles = 0.76 mol
Number of moles of HCl:
Number of moles = mass / molar mass
Number of moles = 50 g/ 36.5 g/mol
Number of moles = 1.4 mol
Now we will compare the moles of Reactant with product.
Zn : ZnCl₂
1 : 1
0.76 : 0.76
Zn : H₂
1 : 1
0.76 : 0.76
HCl : ZnCl₂
2 : 1
1.4 : 1/2×1.4 = 0.7
HCl : H₂
2 : 1
1.4 : 1/2×1.4 = 0.7
Less number of moles of product are formed by HCl it will act limiting reactant.
Answer: -
0.2 Kg
Explanation: -
The equation used by Rhia for the carbon footprint measurement is
C = 0.2 B + 0.1 S
where S miles are by subway, B miles by bus and C is Kg of carbon dioxide.
From the equation we see the coefficient of B is 0.2.
Thus 0.2 Kg of carbon dioxide per mile the bus portion contributes to Rhia's carbon footprint.
