In general terms, exothermic reactions release energy, so the energy goes from the system to the surroundings.
decameters - meters: multiply by 10
meters to meters: multiply by 1
centimeters to meters: divide by 100
millimeters to meters: divide by 1000
For the rows at the bottom:
hectometer row: 100, multiply by 100, 4500
decameter row: 10, multiply by 10, 450
meter row: 1, multiply by 1, 45
decimeter row: 0.1, divide by 10, 4.5
centimeter row: 0.01, divide by 100, 0.45
im guessing theres a millimeter row at the bottom:
millimeter row: 0.001, divide by 1000, 0.045
hope this helps!
Answer:
B.Thermal insulation minimizes energy loses to the atmosphere.
Explanation:
It is important because it helps to stop hit from transferring from the calorimeter to the environment. This would help to have an accurate measurement of the heat that was used in the chemical process. The greatest cause of error that happens in calorimetry is when heat is lost to the environment. To reduce this, you insulate the calorimeter and add a cover.
Answer: both compounds have ionic bond between metal and non-metal
Explanation: both Sr and Mg are earth alkaline metals and form ions Mg^2+
And Sr^2+. Br forms ion Br^- and S ion is S^2+.
Answer:
0.35 atm
Explanation:
It seems the question is incomplete. But an internet search shows me these values for the question:
" At a certain temperature the vapor pressure of pure thiophene (C₄H₄S) is measured to be 0.60 atm. Suppose a solution is prepared by mixing 137. g of thiophene and 111. g of heptane (C₇H₁₆). Calculate the partial pressure of thiophene vapor above this solution. Be sure your answer has the correct number of significant digits. Note for advanced students: you may assume the solution is ideal."
Keep in mind that if the values in your question are different, your answer will be different too. <em>However the methodology will remain the same.</em>
First we <u>calculate the moles of thiophene and heptane</u>, using their molar mass:
- 137 g thiophene ÷ 84.14 g/mol = 1.63 moles thiophene
- 111 g heptane ÷ 100 g/mol = 1.11 moles heptane
Total number of moles = 1.63 + 1.11 = 2.74 moles
The<u> mole fraction of thiophene</u> is:
Finally, the <u>partial pressure of thiophene vapor is</u>:
Partial pressure = Mole Fraction * Vapor pressure of Pure Thiophene
- Partial Pressure = 0.59 * 0.60 atm