B. the reason we must wear seat belts
Answer: The ratio of atoms of potassium to ratio of atoms of oxygen is 4:2
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed, and remains conserved. The mass of products must be same as that of the reactants.
Thus the number of atoms of each element must be same on both sides of the equation so as to keep the mass same and thus balanced chemical equations are written.
K exists as atoms and oxygen exist as molecule which consists of 2 atoms. The ratio of number of atoms on both sides of the reaction are same and thus the ratio of atoms of potassium to ratio of atoms of oxygen is 4:2.
Answer:280.216j/kg°C
Explanation:
Mass of metal=0.0663kg
mass of water=0.395kg
Final temperature=27.4°C
Temperature of metal=241°C
Temperature of water=25°C
specific heat capacity of water=4186j/kg°C
0.0663xax(241-27.4)=0.395x4186x(27.4-25)
0.0663xax213.6=0.395x4186x2.4
14.16168a=3968.328
a=3968.328 ➗ 14.16168
a=280.216j/kg°C
Answer:
1250 J
Explanation:
Work is said to be done when a force causes an object to move over a distance. The amount of work done (W) is calculated by multiplying the force by the distance traveled.
That is;
W = F × d
Where;
W = work done (J or N/m)
F = force (N)
d = distance (m)
Based on the information provided in this question, F = 5000N, d = 0.25m
Hence;
W = F × d
W = 5000 × 0.25
W = 1250J
Therefore, 1250Joules of work is done by the jack.