Answer:
223 g O₂
Explanation:
To find the mass of oxygen gas needed, you need to (1) convert moles Al to moles O₂ (via the mole-to-mole ratio from reaction coefficients) and then (2) convert moles O₂ to grams O₂ (via the molar mass). When writing your ratios/conversions, the desired unit should be in the numerator in order to allow for the cancellation of the previous unit. The final answer should have 3 sig figs because the given value (9.30 moles) has 3 sig figs.
4 Al + 3 O₂ ----> 2 Al₂O₃
^ ^
Molar Mass (O₂): 32.0 g/mol
9.3 moles Al 3 moles O₂ 32.0 g
------------------- x --------------------- x -------------------- = 223 g O₂
4 moles Al 1 mole
Explanation:
According to the law of conservation of mass, mass can neither be created nor destroyed but it can simply be transformed from one form to another.
For example, 
Mass of Na = 23 g/mol
Mass of Cl = 35.5 g/mol
Sum of mass of reactants = mass of Na + mass of Cl
= 23 + 35.5 g/mol
= 58.5 g/mol
Mass of product formed is as follows.
Mass of NaCl = mass of Na + mass of Cl
= (23 g/mol + 35.5) g/mol
= 58.5 g/mol
As mass reacted is equal to the amount of mass formed. This shows that mass is conserved.
As a result, law of conservation of mass is obeyed.
The most simplified meaning within a language is MORPHEME.
In English language, a morpheme refers to a language unit, that is made up of a word or a word elements which can not be further broken down into meaningful smaller parts. Morphemes are the smallest, basic, grammatical unit of a language that have distinct meaning, just as atoms are the smallest unit of elements in chemistry. Examples of morphemes are: sad, joy, depress, excited, etc.
Answer:
0.082g
Explanation:
The following data were obtained from the question:
Heat (Q) = 0.092J
Change in temperature (ΔT) = 0.267°C
Specific heat capacity (C) of water = 4.184J/g°C
Mass (M) =..?
Thus, the mass of present can be obtained as follow:
Q = MCΔT
0.092 = M x 4.184 x 0.267
Divide both side by 4.184 x 0.267
M = 0.092 / (4.184 x 0.267)
M = 0.082g
Therefore, mass of water was present is 0.082.