<span>1) </span><span>What is air pressure? (Answ</span>er: Atmospheric
pressure, sometimes also called barometric pressure, is the pressure within the
atmosphere of Earth.)
<span>2)
</span><span>What
is a barometer and what is it used to measure? <span>(Answer: A barometer is a scientific instrument used in meteorology to
measure atmospheric pressure. Pressure tendency can forecast short term changes in the
weather.)</span></span>
<span>3)
</span><span>How
does air pressure change? <span>(Answer: Millibar values used in
meteorology range from about 100 to 1050. At sea level, standard air pressure in millibars is
1013.2. Weather maps showing the pressure at
the surface are drawn using millibars. ... This change in pressure is
caused by changes in air density, and air density is related to
temperature.)</span></span>
<span>4) </span><span>Why is cooler, drier air related to High
Pressure? <span>(Answer: This is due to density differences
between the two air masses.
Since stronger high-pressure systems contain cooler or drier air, the air mass is denser and flows
towards areas that are warm or moist, which are in the vicinity of low pressure areas in advance of
their associated cold fronts.)</span></span>
<span>5)
</span><span>Why
is warm, moister air related to Low Pressure?
<span>(Answer: When air warms, its molecules scatter.
The air becomes
lighter and rises.)</span></span>
Make sure the equation is always balanced first. (It is balanced for this question already) 6.022 x 10^23 is Avogadro’s number. In one mole of anything there is always 6.022 x 10^23 molecules, formula units, atoms. For one mol of an element/ compound use molar mass (grams).
Multiply everything on the top = 8.61x10^47
Multiple everything on bottom= 1.20x10^24
Divide top and bottom = 7.15x10^23
Answer: 7.15x10^23 mol SO2
1) Compund Ir (x) O(y)
2) Mass of iridium = mass of crucible and iridium - mass of crucible = 39.52 g - 38.26 g = 1.26 g
3) Mass of iridium oxide = mass of crucible and iridium oxide - mass of crucible = 39.73g - 38.26g = 1.47g
4) Mass of oxygen = mass of iridum oxide - mass of iridium = 1.47g - 1.26g = 0.21g
5) Convert grams to moles
moles of iridium = mass of iridium / molar mass of iridium = 1.26 g / 192.17 g/mol = 0.00656 moles
moles of oxygen = mass of oxygen / molar mass of oxygen = 0.21 g / 15.999 g/mol = 0.0131
6) Find the proportion of moles
Divide by the least of the number of moles, i.e. 0.00656
Ir: 0.00656 / 0.00656 = 1
O: 0.0131 / 0.00656 = 2
=> Empirical formula = Ir O2 (where 2 is the superscript for O)
Answer: Ir O2
Answer:
a) the minimun of acetic anhydride required for the reaction is 2.175 g (CH3CO)2O
b) V acetic anhydride = 2.010 mL
Explanation:
C6H4OHCOOH + (CH3CO)2O ↔ C9H8O4 + C2H4O2
⇒ mol salicylic acid = 2.94 g C6H4OHCOOH * ( mol C6H4OHCOOH / 138.121 g ) = 0.0213 mol C6H4OHCOOH
⇒ mol acetic anhydride = 0.0213 mol C6H4OHCOOH * ( mol (CH3CO)2O / mol C6H4OHCOOH ) = 0.0213 mol (CHECO)2O
⇒ g acetic anhydride = 0.0213 mol * ( 102.1 g/mol ) = 2.175 g CH3CO)2O
b) V = 2.175 g (CH3CO)2 * ( mL / 1.082 g ) = 2.010 mL (CH3CO)2O
Answer:
Molecular compounds are pure substances formed when atoms are linked together by sharing of electrons while ionic compounds are formed due to the transfer of electrons.
Molecular compounds are made due to covalent bonding while ionic compounds are made due to ionic bonding.
Explanation:
