Answer:
2407 kJ/mol
Explanation:
Given:
Mass of water = 40.00 kg
= 1.065 °C
Net Heat transfer during heating:
Specific heat of water = 4.187 kJ/kg°C
Q = 178.3662 kJ
Heat gained by water is heat lost by the compound. Thus, heat lost = 178.3662 kJ
Also,
Mass = 4.000 g
Molar mass of 
The formula for the calculation of moles is shown below:
Thus,
<u>Standard heat of formation = 178.3662 kJ / 0.0741 mol=2407 kJ/mol (In correct significant digits)</u>
The elements are identified by the number of protons of the atom, which is its atomic number.
In this case the number of protons 39 (atomic number 39) permit you to identify the element as gallium.
Now, to identify the isotope you tell the name of the element and add the mass number.
The mass number is the sum of the protons and the neutrons.
In this case, the number of neutrons is the original 39 plus the 2 added suddenly, i.e. 39 + 2 = 41, so the mass number is 31 + 41 = 72
Therefore, the isotope is gallium - 72.
Answer: isotope gallium - 72
Answer:
the temperature of the star
Explanation:
The color of stars usually indicates the temperature of the star.
A star that is relatively cold usually shows a typical red color.
The hottest stars have a blue color.
- These star colors have been used by astronomers to determine their temperature.
- A broad spectrum between blue, the hottest color, and red the coldest is used.
- Class O stars are usually the blue colored ones
- Class M is the coldest with red color
Answer:
Water gradually degrades them until the metal parts rust and the other materials deteriorate.
Explanation:
