"The reaction is exothermic and ΔH is negative" can be understood about the reaction and the enthalpy change (ΔH) during the reaction.
<u>Option: D</u>
<u>Explanation:</u>
When the reaction is positive, the process becomes endothermic, i.e. heat appears to be consumed by the system because the reaction products are more enthalpic than the reactants. When the reaction is negative, on the other hand, the process is exothermic, which is the total decrease in enthalpy is caused by heat production. Here the initial temperature is 21.0 C but increase in final temperature to 38.8 C, because if some processes require heat, others must give off heat when they take place.
Find volume of pillow
L=78cm
B=55cm
H=25cm
Now
Mass=5.5kg
Density of water=1000kg/m^3
As it is less than density of water it will float on water
Answer: The density of the material is 2.66 g/mL and it is likely this is made of Aluminum
Explanation:
The first step to know the material of the chunk of metal is to calculate its density. The general formula for density is P (density) = 
. Moreover, in this case, it is known the mass is 37.28 g, but the volume is not directly provided. However, we know the water in the graduated cylinder had a volume of 20.0 mL and this increased to 34.0 mL when the chunk of metal is added, this means the volume of the metal is 14 mL (34.0 mL - 20.0 mL = 14 mL). Now let's calculate the density:
This means the density of this metal is 2.66 g/mL, which can be rounded as 2. 7 g/mL, and according to the chart, this is the density of aluminum. Therefore, this material of this chunk is aluminum.
1 mole ------------- 6.02 x 10²³ atoms
5.10 moles -------- ( atoms sulfur )
atoms sulfur = 5.10 x ( 6.02 x 10²³ ) / 1
atoms sulfur = 3.07 x 10²⁴ / 1
= 3.07 x 10²⁴ atoms of sulfur
hope this helps!
Answer:
2NaCl(l) => 2Na(s) + Cl₂(g)
Explanation:
Electrolysis of melt NaCl to form sodium (Na) metal and chlorine (Cl₂) gas.
This is a class of reaction called 'Decomposition Rxns'. For what it's worth, there are 6 distinct compound types that undergo breakdown by decomposition. The acronym C O A C H E can help remember them.
C - Carbonates => CaCO₃(s) => CaO + CO₂
O - Oxides of Metals => 2Fe₂O₃(s) => 4Fe°(s) + 3O₂(g)
A - Acids (Oxoacids) => H₂CO₃(aq) => CO₂(g) + H₂O(l)
C - Chlorates, Bromates & Iodates => 2KClO₃(s) => 2KCl(s) + 3O₂(g)
H - Hydroxides => Ca(OH)₂(s) => CaO(s) + H₂O(l)
E - Electrolysis => see above electrolysis of NaCl(l)
