Answer:
see attached
Explanation:
Dimensional analysis is useful whenever dimensions are involved. Unless it is quite clear that all of the problem dimensions are consistent (for example, all speeds in miles per hour, or all angles in degrees), dimensional analysis can be useful for keeping the math straight.
Only units of the same dimensions can be added or subtracted. When numbers are multiplied or divided or raised to a power, dimensional analysis can help ensure that the appropriate operations are being used on appropriate numbers. It can also help ensure that dimensions are being combined properly to give appropriate derived dimensions.
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Scientific notation is a way of writing very large or very small numbers compactly. It can also help with "order of magnitude" estimates. If an answer using SI prefixes is appropriate, or if a number can be conveniently expressed in standard form, then scientific notation is usually not required.
On the other hand, SI prefixes may not be appropriate in some cases, or a problem may specify that scientific notation be used for expressing results. In those instances, scientific notation should be used.
Answer: d. More than 6.5 grams of copper (II) is formed, and some copper chloride is left in the reaction mixture.
Explanation: 
As can be seen from the chemical equation, 2 moles of aluminium react with 3 moles of copper chloride.
According to mole concept, 1 mole of every substance weighs equal to its molar mass.
Aluminium is the limiting reagent as it limits the formation of product and copper chloride is the excess reagent as (14-7.5)=6.5 g is left as such.
Thus 54 g of of aluminium react with 270 g of copper chloride.
1.50 g of aluminium react with=
of copper chloride.
3 moles of copper chloride gives 3 moles of copper.
7.5 g of copper chloride gives 7.5 g of copper.
The formula for chromium (III) phosphate trihydrate is CrPO4- 3H20. This compound if in the anhydrous state, exists as a green crystal whereas a hydrated form violet crystal. The formula for cobalt(II) phosphate octahydrate is Co3(PO4)2•8H2O.
Answer: 3.69 × 10^27
Explanation:
Amount of energy required = 7.06 × 10^4 J
Frequency of microwave (f) = 2.88 × 10^10 s−1
Planck's constant (h) = 6.63 × 10^-34 Jᐧs/quantum
Recall ;
Energy of photon = hf
Therefore, energy of photon :
(6.63 × 10^-34)j.s× (2.88 × 10^10)s^-1
= 19.0944 × 10^(-34 + 10) = 19.0944×10^-24 J
Hence, number of quanta required :
(7.06 × 10^4)J / (19.0944 × 10^-24)J
= 0.369 × 10^(4 + 24) = 0.369×10^28
= 3.69 × 10^27
