Endothermic reaction : A reaction in which the system absorb energy, usually in the form of heat
the one that is an endothermic reaction is : D. Thawing ice
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Why does the grass be green
Answer:
3.07 Cal/g
Explanation:
Step 1: Calculate the heat absorbed by the calorimeter
We will use the following expression.
Q = C × ΔT
where,
- C: heat capacity of the calorimeter (37.60 kJ/K = 37.60 kJ/°C)
- ΔT: temperature change (2.29 °C)
Q = 37.60 kJ/°C × 2.29 °C = 86.1 kJ
According to the law of conservation of energy, the heat released by the candy has the same magnitude as the heat absorbed by the calorimeter.
Step 2: Convert 86.1 kJ to Cal
We will use the conversion factor 1 Cal = 4.186 kJ.
86.1 kJ × 1 Cal/4.186 kJ = 20.6 Cal
Step 3: Calculate the number of Cal per gram of candy
20.6 Cal/6.70 g = 3.07 Cal/g
<span>Answer:
mol Al2O3 x 1 mol Al/ 2 mol Al2O3= .25 mol Al
The balanced equation tells us that it takes 4 moles of Al to produce 2 moles of Al2O3.
0.50 moles Al2O3 x (4 moles Al / 2 moles Al2O3) = 1.0 moles Al
1.0 moles Al x (27.0 g Al / 1 mole Al) = 27.0 g Al</span>
Covalent bonds can be classified as nonpolar and polar covalent given the electronegativity difference between two atoms (ΔEN).
Nonpolar covalent bond electrons are shared equally between two atoms, polar covalent bond electrons are shared unequally, atoms have partial charges, ionic bond electrons are completely transferred to one atom, full charges present. Therefore, the greater the electronegativity difference, the greater the bond polarity. Let's determine the types of bonds present in the compounds and arrange the ones with polar covalent in order of increasing ΔEN. Sulfur and oxygen are both nonmetals so the substance is covalent. Sulfur has EN = 2.5 and oxygen has EN = 3.5. Since there is an electronegativity difference, the S−O bonds in the substance can be classified as polar covalent bonds.
Learn more about polar covalent bond here:
brainly.com/question/25150590
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