Answer: I think that you have to find it in your lesson
Explanation:
CuCl2+F2—>CuF2+Cl2.
This is a single replacement because there is one compound and one element. Picture Cu as ‘A’ Cl2 as ‘B’ and F2 as ‘C.’ So AB+C—>AC+B. A and B “broke up” and that resulted to A going with C to create the compound CuF2 leaving Cl2 alone.
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
Answer:
Kr is a Noble Gas. Na is an alkali metal. F is halogen.
Group 17 is halogens. Inert is Noble Gases. Odourless and colourless is Noble Gases. Alkali metals do not occur freely in nature. Alkali metals are malleable
Explanation:
Answer;
-(3) an atom in an excited state
Explanation;
-An electron in a sodium atom gains enough energy to move from the second shell to the third shell. The sodium atom becomes an atom in an excited state.
-Ground state is the lowest allowable energy state of an atom. When electrons are subjected to stimuli like heat, light or electricity an electron may jump to a higher energy level, which is the excited state. Excitation is the elevation in energy level above the baseline energy state.
