Answer:
The two samples have identical properties because they are the samples of the same element. Intensive properties are properties of matter that do not change depending on the amount of matter. Luster, reactivity, and ductility are all intensive properties. That is why the two samples can be different sizes or shapes, but have identical properties.
Answer:
90.5mL is the volume of the gas at STP
Explanation:
It is possible to find volume of a gas when conditions of temperature and pressure change using combined gas law:
Where P is pressure, V is volume and T is absolute temperature. 1 is initial conditions and 2 final conditions.
If initial conditions are 1.08atm, 80.0mL and absolute temperature is (-12.5°C + 273.15) = 260.65K.
And STP are 1atm of pressure and 273.15K of absolute temperature. Replacing:
V₂ = <em>90.5mL is the volume of the gas at STP</em>
Answer:
-1.71 J/K
Explanation:
To solve this problem we use the formula
ΔS = n*ΔH/T
Where n is mol, ΔH is enthalpy and T is temperature.
ΔH and T are already given by the problem, so now we calculate n:
Molar Mass C₂H₅OH = 46 g/mol
2.71 g C₂H₅OH ÷ 46g/mol = 0.0589 mol
Now we calculate ΔS:
ΔS = 0.0589 mol * −4600 J/mol / 158.7 K
ΔS = -1.71 J/K
The type of substances that would make good conductors would be substances that has greater density. This would mean that the particles of the substance are much closer to each other and would allow the free flow of the electrons in the substance. With this, current would be able to flow freely.
Answer:
Making oxygen
Oxygen can be made from hydrogen peroxide, which decomposes slowly to form water and oxygen:
hydrogen peroxide → water + oxygen
2H2O2(aq) → 2H2O(l) + O2(g)
The rate of reaction can be increased using a catalyst, manganese(IV) oxide. When manganese(IV) oxide is added to hydrogen peroxide, bubbles of oxygen are given off.
Apparatus arranged to measure the volume of gas in a reaction. Reaction mixture is in a flask and gas travels out through a pipe in the top and down into a trough of water. It then bubbles up through a beehive shelf into an upturned glass jar filled with water. The gas collects at the top of the jar, forcing water out into the trough below.
To make oxygen in the laboratory, hydrogen peroxide is poured into a conical flask containing some manganese(IV) oxide. The gas produced is collected in an upside-down gas jar filled with water. As the oxygen collects in the top of the gas jar, it pushes the water out.
Instead of the gas jar and water bath, a gas syringe could be used to collect the oxygen.
