Heat_1: Get the ice to 0 degrees
Convert 7 kg to grams
7 kg [1000 grams / 1 kg] = 7000 grams
Heat needed to get the the ice from - 9 to 0
deltat = 0 - -9 = 9 degrees
m = 7000 grams
c = 2.1 joules/gram
Heat_1 = m*c*deltat
Heat_1 = 7000 * 2.1 * 9
Heat_1 = 132,300 joules
Heat_2: Melt the ice.
There is no temperature change. The formula is 333 j/gram
Formula: H = mass * constant
H = 7000 g * 333 J / gram
H = 2331000 joules
Heat_3: Total amount of Joules needed.
2331000 + 132300 = 2 463 300 joules
Convert to Megajoules
2 463 300 joules * 1 megajoule / 1000000 = 2.63 megajoules.
1 mol is equal to 6.02×10∧23 molecules.
first put in the calculator 4.81042 × 6.02 then hit EXP or 2nd then EE. (Depends on the type of calculator). then put in 23 and press equal.
The calculator will says 2.89587284×10∧24.
So the answer will be 2.90×10∧24.
I mot sure if the 2.90 is correct but it is close to the answer. it really depends how you want to round it. As long as the decimals are close the answer doesn't matter. Hope this helps. Please mark as Brainliest.
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Answer:
i am not so sure
Explanation:but you r beautiful
Answer:
the pair of isotopes are b and e
the element with mass no of 19 is C
the element with atomic no 7is D
Explanation:
B and E are isotopes bcos they have the same atomic no, i.e no of protons. They bother have atomic no of 17 BUT have different mass no i.e sum of neutrons and protons.
(b)C is correct because the sum of the protons and neutrons is 19
(c) D because it has 7 protons
