The temperature when ice melts is 32 degrees Fahrenheit.
The formula will be AI2O3
Answer:
A. there is an isotope of lanthanum with an atomic mass of 138.9
Explanation:
By knowing the different atomic masses of both Lanthanum atoms, we can not tell anything about their occurence in nature. Therefore, all the last three options are incorrect. Because, the atomic mass does not tell anything about the availability or natural abundance of an element.
Now, the isotopes of an element are those elements, which have same number of electrons and protons as the original element, but different number of neutrons. Therefore, they have same atomic number but, different atomic weight or atomic masses.
Hence, by looking at an elements having same atomic number, but different atomic masses, we can identify them as isotopes.
Thus, the correct option is:
<u>A. there is an isotope of lanthanum with an atomic mass of 138.9.</u>
Answer:
<h3>The answer is 32 g/cm³</h3>
Explanation:
The density of a substance can be found by using the formula
From the question
mass = 768 g
volume = 24 cm³
We have
We have the final answer as
<h3>32 g/cm³</h3>
Hope this helps you
Answer: The number of grams of 
in 1620 mL is 1.44 g
Explanation:
According to ideal gas equation:
P = pressure of gas = 1 atm (at STP)
V = Volume of gas = 1620 ml = 1.62 L (1L=1000ml)
n = number of moles = ?
R = gas constant =
T =temperature =
Mass of hydrogen =
The number of grams of in 1620 mL is 1.44 g
