The reactivity of a metal is determined by how tightly the metal holds onto the electrons in the outermost energy levels (valence electrons)
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
The answer is 4.9 moles.
Solution:
Using the equation for boiling point elevation Δt,
Δt = i Kb m
we can rearrange the expression to solve for the molality m of the solution:
m = Δt / i Kb
Since we know that pure water boils at 100 °C, and the Ebullioscopic constant Kb for water is 0.512 °C·kg/mol,
m = (105°C - 100°C) / (2 * 0.512 °C·kg/mol)
= 4.883 mol/kg
From the molality m of the solution of salt added in a kilogram of water, we can now find the number of moles of salt:
m = number of moles / 1.0kg
number of moles = m*1.0kg
= (4.883 mol/kg) * (1.0kg)
= 4.9 moles
Sulphate ion is used but fornyour kind information there ain't no place
The density of a solid object that has a mass of 1.62 lb and a volume of 190 mL is 3.87g/mL.
<h3>How to calculate density?</h3>
Density is the measure of the mass of matter contained by a unit volume. It can be calculated by dividing the mass of the substance by its volume.
According to this question, a solid object is said to have a mass of 1.62 lb and a volume of 190 mL.
1 pound = 453.592 grams
1.62 Ibs is equivalent to 734.82 grams
Density of the solid object = 734.82 grams ÷ 190 mL
Density = 3.87g/mL
Therefore, the density of a solid object that has a mass of 1.62 lb and a volume of 190 mL is 3.87g/mL.
Learn more density at: brainly.com/question/20337365
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