Answer:
We need 1.1 grams of Mg
Explanation:
Step 1: Data given
Volume of water = 78 mL
Initial temperature = 29 °C
Final temperature = 78 °C
The standard heats of formation
−285.8 kJ/mol H2O(l)
−924.54 kJ/mol Mg(OH)2(s)
Step 2: The equation
The heat is produced by the following reaction:
Mg(s)+2H2O(l)→Mg(OH)2(s)+H2(g)
Step 3: Calculate the mass of Mg needed
Using the standard heats of formation:
−285.8 kJ/mol H2O(l)
−924.54 kJ/mol Mg(OH)2(s)
Mg(s) + 2 H2O(l) → Mg(OH)2(s) + H2(g)
−924.54 kJ − (2 * −285.8 kJ) = −352.94 kJ/mol Mg
(4.184 J/g·°C) * (78 g) * (78 - 29)°C = 15991.248 J required
(15991.248 J) / (352940 J/mol Mg) * (24.3 g Mg/mol) = 1.1 g Mg
We need 1.1 grams of Mg
City B is at a higher temperature because as you go higher in altitude the boiling point of water becomes lower.
It can be done. Normally the boiling point of water is 100°C. It will boil at temperature greater than 100°C more quickly. Water can be boiled at 95°C but for that the atmospheric pressure of the water should be decreased which will decrease the boiling point of water.
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Concept :</h3>
To boil water at 95°C, decrease the atmospheric pressure.
At 105°C, the water will be boiling quickly than normal at 100°C.
Heterogenous mixtures are unevenly mixed. Like oil and vinegar in vinaigrette if it is not emulsified well enough and they separate. Any case where two things are not evenly distributed within each other.
Homogenous mixtures are evenly mixed throughout. Like salt water or kool-aid (when it's mixed).
Hope this helps!
Answer:
Metallic character decreases, and electronegativity increases.
Explanation:
Hello!
In this case, according to the organization of the periodic table, we can see that from left to right, the electronegativity increases as nonmetals are able to attract electrons more easily than metals.
Moreover, in contrast to the previous periodic trend, the metallic character decreases from left to right because the elements tend to decrease the capacity to lose electrons and consequently start attracting them.
Thus, the answer would be: "Metallic character decreases, and electronegativity increases".
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