Answer:
The reason why atomic mass is usually not a whole number is because it is a weighted average of the mass numbers of isotopes
Explanation:
Answer:
a) Limiting: sulfur. Excess: aluminium.
b) 1.56g Al₂S₃.
c) 0.72g Al
Explanation:
Hello,
In this case, the initial mass of both aluminium and sulfur are missing, therefore, one could assume they are 1.00 g for each one. Thus, by considering the undergoing chemical reaction turns out:

a) Thus, considering the assumed mass (which could be changed based on the one you are given), the limiting reagent is identified as shown below:

Thereby, since there 1.00g of aluminium will consume 0.0554 mol of sulfur but there are just 0.0156 mol available, the limiting reagent is sulfur and the excess reagent is aluminium.
b) By stoichiometry, the produced grams of aluminium sulfide are:

c) The leftover is computed as follows:

NOTE: Remember I assumed the quantities, they could change based on those you are given, so the results might be different, but the procedure is quite the same.
Best regards.
The heat transfer just occurred is mainly conduction.
Conduction happens when two objects are in contact with each other. In the hotter object, the molecules and/or free electrons have a higher kinetic energy, thus they'll travel and collide into other molecules, resulting in spreading the energy to the other object.
The heat transfer happens until thermal equilibrium, where both objects have the same temperature and their molecules have the same kinetic energy rate.
In addition, radiation is also happening since everything that has a higher temperature than the environment is a net emitter. They release electromagnetic waves that turn out to be radiation. These occur even without the presence of air.
4 grams , mass cannot be created or destroyed. it has to be the same on both sides of the equation
Answer:
A. 8.4
Explanation:
[OH⁻] = 2.6 × 10⁻⁶ Take the negative log of each side
-log[OH⁻] = pOH = 5.59 Apply the pH/pOH relation
pH + pOH = 14.00 Insert the value of pOH
pH + 5.59 = 14.00 Subtract 5.59 from each side
pH = 14.00 -5.59 = 8.41