Http://www.geologyin.com/2014/11/how-to-identify-minerals-in-10-steps.html
The correct answers are as follows:
1. Aluminium will not be useful as food wrapping if it has a much lower melting point.
Aluminum is a metallic element that is malleable and soft, thus, it is easy to beat it into thin sheet, which are used to package food. The thin sheet is called aluminium foil. Aluminum is useful as a food wrapping because it has high temperature and thus, it does not react with food (the hotness of the packaged food is not capable of melting the metal). If the melting point of aluminium is lower, this implies that little temperature, such as the one from hot food will be able to melt aluminum foil, thus allowing the food to be contaminated with the metal.
2. When bleach react with fabric dye chemical change occur in the fabric.
The major element in bleach is chlorine. When laundry bleach is added to a fabric, the chlorine component of the bleach will react with the fabric dye and cause a colour change in the fabric. This type of change is called chemical change, because the original colour of the fabric can not be recovered.
3. Every substance has specific properties, which can be used to identify it. Two of such specific properties are melting point and boiling point. Melting point refers to a specific temperature at which a solid substance will melt while boiling point refers to a specific temperature at which a liquid substance will boil and turn to steam.
Water for instance has a boiling point of 100 degree Celsius. To find out if an unknown substance is water, one can determine the boiling point of such liquid. A boiling point of 100 degree Celsius will strongly signify that the substance is probably water. The same thing applies to melting point. If the specific boiling and melting point of substances are known, then they can be used to identify them.
Answer:
Free energy change is -7.500248 kJ/mol
Explanation:
If we have the enthalpy change and entropy change, we can find the free energy change using the equation,
ΔG = ΔH - TΔS
Temperature in K = 25°C + 273 = 298 K
ΔH for NaI = -7.50 kJ/mol
ΔS for NaI = 74 J/K mol = 0.074 kJ/K mol
Plugin the above values in the equation, we will get,
ΔG = -7.5 kJ/mol - 0.074 kJ/K mol / 298 K
= -7.5 kJ/mol - 0.000248 kJ/mol
= -7.500248 kJ/mol
<u>Answer:</u> The molar concentration of ethylenediminediacetic-dihydrate and sodium ions in solution is 0.1976 M and 0.3952 M respectively.
<u>Explanation:</u>
To calculate the molarity of solution, we use the equation:
We are given:
Mass of solute (disodium ethylenediaminetetraacetic acid dihydate) = 36.7845 g
Molar mass of disodium ethylenediaminetetraacetic acid dihydate = 372.24 g/mol
Volume of solution = 0.5000 L
Putting values in above equation, we get:
As, 1 mole of disodium ethylenediaminetetraacetic acid dihydate produces 2 moles of sodium ion and 1 mole of ethylenediminediacetic-dihydrate.
Concentration of ethylenediminediacetic-dihydrate in solution = 
Concentration of sodium ions in solution = 
Hence, the molar concentration of ethylenediminediacetic-dihydrate and sodium ions in solution is 0.1976 M and 0.3952 M respectively.
As the temperature of a liquid increases, its viscosity decreases.
