Answer and Explanation:
Two hydrogen atoms, each containing one electron, approach each other in the formation of a molecule of hydrogen. Each atom needs a total of two electrons to fill their outermost energy level and make them stable. The best choice is to share their single electrons. Hence, a pair of bonding electrons is shared between the hydrogen atoms in the molecules.
This constitutes a single covalent bond. Hence, the correct option is B)
Grams ethanol = 33 ml times .789 gms/ml = 26.037 gms
<span>Moles ethanol = 26.037 gms / 46 gms/mole = .57 moles </span>
<span>Moles water = 67 ml or 67 grams/18 gms/mole = 3.22 moles </span>
<span>total moles = .57 + 3.72 = 4.29 moles </span>
<span>Mole fraction ethanol = .57 moles ethanol / 4.29 moles total = 0.13</span>
<span>Moles fraction water = 3.72 moles water / 4.29 moles total = 0.87</span>
<span>Partial pressure of ethanol = mole fraction ethanol (.13) _ times VP ethanol 43.9 torr) = 5.707 torr </span>
<span>partial pressure water = mole fraction water .87) times VP water (l7.5 torr) = 15.23 torr </span>
<span>Total vapor pressure over solution = 5.71 torr + 15.23 torr = 20.94 torr</span>
Answer: 400K
Explanation:
Given that,
Original volume of balloon V1 = 3.0L
Original temperature of balloonT1 = 27°C
Convert the temperature in Celsius to Kelvin
(27°C + 273 = 300K)
New volume of balloon V2 = 4.0L
New temperature of balloon T2 = ?
Since volume and temperature are given while pressure is constant, apply the formula for Charle's law
V1/T1 = V2/T2
3.0L/300K = 4.0L/T2
To get the value of T2, cross multiply
3.0L x T2 = 4.0L x 300K
3.0LT2 = 1200LK
Divide both sides by 3.0L
3.0LT2/3.0L = 1200LK/3.0L
T2 = 400K
Thus, at a temperature of 400 Kelvin, the balloon would have a volume of 4.0L.
<span>They utilize and make use of the scientific method in order to have clear basis and evidence for their investigations. Research method is always used to answer every scientific inquiry and in gaining evidential data or knowledge. The scientific method has the following process or at least undergoes the process of
1. Observation</span>
<span>2. Hypothesis </span>
<span>3. Experimentation </span>
<span>4. Interpretation of data </span>
<span>5. Evaluating the data </span>
<span>6. Passing and recording the data </span>
<span>These steps are crucial and the empirical data that these scientists obtain are very important to keep that is why research paper, thesis and dissertations exists.<span>
</span></span>
Answer:
CaCO₃ built up in hot water pipes
Explanation:
The hardness of water is classified as;
Permanent Hard Water:
In this the mineral content cannot be removed by boiling. This water contains mainly following,
Calcium Sulfate CaSO₄
Calcium Chloride CaCl₂
Magnesium Sulfate MgSO₄
Magnesium Chloride MgCl₂
These salts does not precipitate out on heating water.
Temporary Hard Water:
In this water the mineral content can be removed by boiling. This water contains mainly following,
Calcium Bicarbonate Ca(HCO₃)₂
Calcium Carbonate CaCO₃
Magnesium Bicarbonate Mg(HCO₃)₂
Magnesium Carbonate MgCO₃
These salts does not precipitate out on heating water. i.e.
Ca(HCO₃)₂ -------heat------> CaCO₃ + CO₂ + H₂O
The CaCO₃ are formed in the form of scales.
Result:
Hence, we can say that that CaCO₃ built up in hot water pipes.
