Answer: Thus 663 J of heat is released when 27.6 g 
cools from 83.1 °C to 55.6 °C
Explanation:
The quantity of heat required to raise the temperature of a substance by one degree Celsius is called the specific heat capacity.
Q = Heat released = ?
m = mass of substance = 27.6 g
C = specific heat capacity = 
Initial temperature= 
= 
Final temperature = 
= 
Change in temperature ,
Putting in the values, we get:
As the value of q is negative, it means the heat has been released and it is 663J
57 - True
58 - True
59 - True
60 - Fe and O
61 - Sr and F
62 - <span>both ionic and covalent bonds
Hope this helps!</span>
Answer:
1.35 moles of O²⁻
21.6 grams of O²⁻
Explanation:
We know that the charge on Aluminium ion is +3 (i.e. Al³⁺) while, the charge on Oxide ion is -2 (i.e. O²⁻). Therefore, the overall neutral Al₂O₃ compound has 2 Al³⁺ ions and 3 O²⁻ ions. Since, we can say that,
1 mole of Al₂O3 contains = 3 moles of O²⁻ ions
So,
0.450 moles of Al₂O₃ will have = X g of O²⁻
Solving for X,
X = 0.450 mol × 3 mol ÷ 1 mol
X = 1.35 moles of O²⁻
As the mass of an atom is mainly due to the presence of protons and neutrons hence, the addition of two electrons (-ve 2 shows two gained electron) to Oxygen will make a negligible change to the atomic masss of Oxygen because electron is said to be almost 1800 times lighter than proton. Hence, the ionic mass of O²⁻ will be 16 g/mol and the mass of given moles is calculated as,
Mass = Moles × Ionic Mass
Mass = 1.35 mol × 16 g/mol
Mass = 21.6 g
Answer:
Carcinogens are difficult to identify because there may be a long lag time between exposure to the agent and the detectable onset of cancer
Explanation:
quizlet.com/193673418/environmental-chapter-9-flash-cards/
Explanation:
vertical columns and horizontal rows, hope it helps
