Answer:
11.45kcal/g
2.612 × 10³ kcal
Explanation:
When a compound burns (combustion) it produces carbon dioxide and water. The combustion of 2-methylheptane can be represented by the following balanced equation:
2 C₈H₁₈ + 25 O₂ ⇄ 16 CO₂ + 18 H₂O
It releases 1.306 × 10³ kcal every 1 mol of C₈H₁₈ that is burned.
<em>What is the heat of combustion for 2-methylheptane in kcal/gram?</em>
We know that the molar mass of C₈H₁₈ is 114.0g/mol. Then, using proportions:
<em>How much heat will be given off if molar quantities of 2-methylheptane react according to the following equation? 2 C₈H₁₈ + 25 O₂ ⇄ 16 CO₂ + 18 H₂O</em>
In this equation we have 2 moles of C₈H₁₈. So,
1. Al(C₂H₅)₂OCl₃
Al(C₂H₅)₂OCl₃ is made from 5 different elements. They are Al, C, H, O and Cl. Number of atoms in each element can be found as follows.
number of Al atoms = 1
number of C atoms = 2 x 2 = 4
number of H atoms = 5 x 2 = 10
number of O atoms = 1
number of Cl atoms = 3
<span>
Total number of atoms = 1 + 4 + 10 + 1 + 3 = 19
2. </span>BCl₃<span>
BCl</span>₃ is a simple neutral molecule. It consists of 2 different elements as B and Cl. Total number of atoms is 4. Number of atoms can be calculated as follows.
number of B atoms = 1
number of Cl atoms = 3
Total number of atoms = 1 + 3 = 4<span>
3. </span>H₂O + H⁺
H₂O makes H₃O⁺ (hydronium ion) with H⁺ which is a positive ion. H₃O⁺ consists of two different elements as H and O. Number of atoms are as follows.
number of H atoms = 3
number of O atoms = 1
Total number of atoms = 3 + 1 = 4
Explanation:
<h3>hahahahaha Hindi ko alam thanks nalang sa point</h3>
The balanced equation for the reaction is as follows;
Zn + 2HCl --> ZnCl₂ + H₂
stoichiometry of Zn to HCl is 1:2
limiting reagent is the reactant that is fully consumed in the reaction.
the amount of product formed depends on amount of limiting reactant present.
The excess reactant is when it has been provided in excess and only a fraction of the provided amount is used up in the reaction.
Amount of Zn moles - 0.5 mol
Amount of HCl moles - 0.6 mol
If Zn is provided, number of HCl moles reacted - 0.5 x 2 = 1.0 mol of HCl is required, but only 0.6 mol of HCl is provided.
HCl is therefore the limiting reactant,
Number of Zn moles required - 0.6 mol /2 = 0.3 mol
But 0.5 mol are given, therefore 0.2 mol of Zn is in excess
Answer:
3:2, B
Explanation:
The mole ratio is simply the coefficients in a balanced chemical reaction and their relation to each other.
One simple way to easily know b is the correct answer is to look at the units for the answer choices. A is a ratio of Fe to Fe, C is a ratio of Mg to Fe, and d is a ratio of Mg to Fe. That alone must mean B is the correct answer.
We can also use the definition of a mole ratio, as stated above. Given that this equation is balanced, the mole ratio is simply the ratio of the coefficients, and is thus 3:2.
