Answer:
Acceleration is :
a = 2.89 m/s2
Explanation:
Acceleration : It is the change in the velocity of the object per unit time.
The object starts from the rest , so the initial velocity of the object is zero.
Initial velocity , u = 0
Final velocity = 100 km/h
Change the velocity to m/s because[ time unit is in second(9.60 s)]
1 km = 1000 m
1 hour = 60 x 60 sec = 3600 sec
v = 27.78 m/s
u = 0 m/s
time = 9.60 s
The acceleration"a" is calculated using :
H₂ + ½O₂ → H₂O
2g → 18g
So, 18g water needs 2g H₂
So, 1g water needs 2/18g H₂
So, 180g water needs 2/18 x 180g H₂
→ 20 litres of H₂
Explanation:
Expresa los gramos de soluto por cada 100 gramos de disolución. Porcentaje masa = masa de soluto___ x 100 masa de la disolución Cuando trabajamos con la masa, podemos sumar el soluto y el disolvente para obtener la disolución.
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>
A mixture is a substance made by combining two or more different materials in such a way that no chemical reaction occurs.
A mixture can usually be separated back into its original components. Some examples of mixtures are a tossed salad, salt water and a mixed bag of M&M's candy.
