Answer:
Density of aluminum is 2.699 g/cm^3
Explanation:
Density of a given material can be defined as the mass of the substance present in a unit volume. Mathematically it can be expressed as:
Units: g/cm^3 or kg/m^3
Aluminum (Al) is one the lightest element and is known to have a density of 2.699 g/cm^3
Answer:
pH = 8.1
Explanation:
Assuming that we are at 25 degrees Celsius, pH + pOH = 14.
We can then plug in the given pOH and solve for pH:
pH + pOH = 14
pH + 5.9 = 14
pH = 14 - 5.9 = 8.1
First figure out how many grams must freeze and then convert the grams to moles.
<span>Hf = -334 J/g. Convert this to KJ/g by dividing by 1000. (There are 1000 Joules in a kJ). </span>
<span>Hf = -334 J/g ÷ 1000 J/kj = -0.334 kJ/g </span>
<span>Now, divide 100 kJ by -0.334 kJ/g (see how the units are lining up?) </span>
<span>100 kJ ÷ -0.334 kJ/g = 299 g </span>
<span>Now convert this to moles by dividing by the molecular weight of water (18.0g/mole). </span>
<span>299 ÷ 18.0 = 16.6 moles </span>
The two molecules will only react if they have enough energy. By heating the mixture, you are raising the energy levels of the molecules involved in the reaction. Increasing temperature also means the molecules are moving around faster and will therefore "bump" into each other more often.
