Answer:
A. B. C.D.-allnswers 4 answers
Explanation:
Chemical compound, any substance composed of identical molecules consisting of atoms of two or more chemical elements. ... The fundamental principle of the science of chemistry is that the atoms of different elements can combine with one another to form chemical compounds.
Answer:
Na₂CO₃ · 10H₂O
Explanation:
The formula for sodium carbonate hydrate is:
Na₂CO₃ · xH₂O
The unknown "x" is the number of water molecules contained in the hydrate.
To find "x" we have to use the hydrogen percentage in the sample, 7.05 % H.
First we calculate the molecular weight of Na₂CO₃ · xH₂O:
molecular weight of Na₂CO₃ · xH₂O = 23 × 2 + 12 + 16 × 3 + 18x
molecular weight of Na₂CO₃ · xH₂O = 106 + 18x g/mole
Now we devise the fallowing reasoning tanking in account 1 mole of Na₂CO₃ · xH₂O:
if in 106 + 18x grams of Na₂CO₃ · xH₂O we have 2x grams of hydrogen
then in 100 grams of Na₂CO₃ · xH₂O we have 7.05 grams of hydrogen
106 + 18x = (100 × 2x) / 7.05
106 + 18x = 28.4x
106 = 28.4x - 18x
106 = 10.4x
x = 106 / 10.4
x = 10.2 ≈ 10
The formula for the washing soda is Na₂CO₃ · 10H₂O.
Answer:
The Bowen's reaction series describes how minerals form in sequential order, forming at higher temperature to a lower temperature. There are two branches of crystallization, one is the continuous branch that is on the right and the other is the discontinuous branch that is on the left.
The minerals that are at the top of the Bowen's reaction series forms at a higher temperature.
In the discontinuous branch, the first mineral to crystallize from the melt is Olivine that forms at a higher temperature of about 1400°C. After crystallization, some melt remains and undergoes fractional crystallization leading to the formation of Pyroxene. Again, with the remaining melt, it reacts and forms Amphibole, followed by Biotite (mica).
In the continuous branch, the first minerals to form are the calcium-rich minerals and successively forms sodium-rich minerals. These minerals that form at a higher temperature are basic in nature and gradually change into acidic minerals.
From both the branches, it commonly forms the mineral Potassium feldspar. After this, the remaining melt combines with the magma and forms Muscovite (Mica), and at a temperature of about 650°C, it forms a more resistant and stable mineral known as the Quartz.
Answer:
13 kJ
Explanation:
Use the following formula where Q is the Joules needed, m is the mass of the substance, c is the heat capacity, and ΔT is the change in temperature.
Q = mcΔT
The heat capacity of water is 4.186 J/g°C. The mass of water is 234 g. The change in temperature is 13.3°C.
Q = mcΔT
Q = (234 g)(4.186 J/g°C)(13.3°C)
Q = 13,027 J
Since the answer is in Joules, convert to kiloJoules.
13,027 J = 13.027 kJ ≈ 13 kJ
