Answer:
∴ Q = -7.52kCal
Explanation:
Using the formula for specific heat capacity:
Q = mcΔT
where ΔT = change in temperature (final - initial) = (0 - 100)°C = -100°C
m = mass (g) = 75g
c = specific heat capacity = 4.2 J/g°C in water
⇒ Q = 75 × 4.2 × -100
= -31,500J
But 1J - 0.000239kCal
<u>∴ Q = -7.52kCal</u>
<u />
Let me know if I can be of further assistance.
The atomic number,atomic mass,valence electrons and the formula for calculating the number of neutrons is also given.The following table has been completed below in the attachment.
Explanation:
Atomic Number:the number of protons /electrons present in the nucleus of an atom is called the atomic number.
Mass Number/Atomic Mass:the number of protons and neutrons present in a nucleus
<u>Example:</u>
;here;6 implies the atomic number and 12 implies the mass number/atomic mass
<u><em>No.of neutrons=Mass number-Number of protons</em></u>
Valence electrons:the number of electrons present in the outer most shell of an atom are called valence electrons
<u>Example:</u>If we consider a carbon atom;as its <em>e</em><em>lectronic configuration is2,4 and</em> it belongs to 4th group.Therefore the number of valency electrons in carbon is <u>4.</u>
The substances present before the reaction are the reactants. (As the reaction goes through, the substances that are produced are called the products of the reaction).
Answer:
Below:
Explanation:
To calculate an energy change for a reaction: add together the bond energies for all the bonds in the reactants - this is the 'energy in' add together the bond energies for all the bonds in the products - this is the 'energy out.
Hope it helps....
It's Muska
Answer:
d. 103.3
Explanation:
In the given question, the National Weather Service routinely supplies atmospheric pressure data to help pilots set their altimeters. And the units of atmospheric pressure used for reporting the atmospheric pressure data are inches of mercury. For a barometric pressure of 30.51 inches of mercury, we can calculate the pressure in kPa as follow:
In principle, 3.386 kPa is equivalent to the atmospheric pressure of 1 inch of mercury. Thus, 30.51 inches of mercury is equivalent to 30.51 in *(3.386 kPa/1 in) = 103.307 kPa.
Therefore, a barometric pressure of 30.51 inches of mercury corresponds to _____103.3_____ kPa.