Answer:
chemical energy is stored in the wood before combustion.
Answer:
Avogadro number of representatives particles is equal to one mole.
Explanation:
The number 6.022 × 10²³ is called Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
For example,
18 g of water = 1 mole = 6.022 × 10²³ molecules of water
17 g of ammonia = 1 mole = 6.022 × 10²³ molecules of ammonia
12 g of carbon = 1 mole = 6.022 × 10²³ atoms of carbon
1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen
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:
C) 3.3 x 104 grams
Explanation:
1 mole of water contains 6.02 × 10^23 atoms
1.1 × 10^27 atoms will contain;
1.1 × 10^27 ÷ 6.02 × 10^23
= 0.1827 × 10^( 27 - 23)
= 0.1827 × 10^(4)
= 1.827 × 10³ moles of water.
To convert mole to mass in grams, we use the formula;
mole (n) = mass (m) ÷ molar mass (MM)
Molar mas of water (H2O) = 1(2) of H + 16 of O = 18g/mol
mole = mass/molar mass
1.827 × 10³ = mass / 18
mass = 1.827 × 10³ × 18
mass = 32.886 × 10³
mass = 3.286 × 10⁴
mass = 3.3 × 10⁴ grams
