Cast iron is more brittle than pure iron
Answer:
Option (A) : Positive
Explanation:
A combustion reaction will always be associated with a change in entropy that is Positive due to the gaseous products released. Hence, there is a large positive entropy change.
Answer: first option, the work output of the hairdryer will be less than the work input.
Explanation:
1) The work output measured in watts is the power of hair dryer measured in joules per second.
2) The hair dryer converts electrical energy from the wall outlet to mechanical and thermal energy: hot wind.
3) Nevertheless, you can never expect a 100% efficiency of the machines: due to friction, some energy is converted into useless energy.
So, efiiviency = power output / power input< 1 ⇒
power output = work output / time
input power = work input / time
⇒ work output / work input < 1
⇒ work output < work input.
Which is the first option: the work output of the hairdryer will be less than the work input
Based on octet rule, elements would fill up their
outermost shell with 8 electrons to be stable. In this case, Carbon has 4
valence on its outer shell, Hydrogen has only 1 valence, while Bromine has 7. Therefore
the total valence electrons are:
total valence = 4*4 + 1*6 + 7*2 = 16 + 6 + 14
<span>total valence = 36</span>