Answer:
See below
Explanation:
Reactions require successful collisions between elements or molecules. A rise in temperature increases the movement of molecules. The more movement, the more collisions. The more collisions, the more reactions. The collisions release energy as heat which warms the flask and so on.
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.
The Atomic Number and Atomic Mass of ²⁸Si₁₄ are 14 and 28 respectively.
Atomic Number:
Atomic Number of Element is the Number of Protons contained by the Element. So, there are 14 Protons in ²⁸Si₁₄.
Atomic Mass:
Atomic Mass of Element is the total number of Protons and Neutrons present in the Nucleus of that element.
So,
Atomic Mass = # of Protons + # of Neutrons
As the Atomic mass of ²⁸Si₁₄ is 28 and it has 14 protons, So # of Neutrons are calculated as,
# of Neutrons = Atomic Mass - # of Protons
# of Neutrons = 28 - 14
# of Neutrons = 14
Result:
In ²⁸Si₁₄ Number of Neutrons are 14, Number of Protons are 14.
Z = 14 , n = 14
Answer:
Explanation:
Hello there!
In this case, considering that the heat has two forms, sensible (variable temperature) and latent (constant temperature), we can notice that phase changes account for latent heat as the temperature remains the same. In such a way, given the enthalpy of vaporization of water, 40.67 kJ/mol, the enthalpy of condensation (reverse process) is the negative value, -40.67 kJ/mol; therefore, the associated latent heat would be:
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