Answer:
The atomic mass of lead is: 207.216 u
Explanation:
data Isotopes mass percent
1 203.97302 1.4
2 205.974444 24.1
3 206.97587 22.1
4 207.97663 52.4
atomic mass = (203.97302x 0.014) + (205.974444 x 0.241) +
(206.97587 x 0.221) + (207.97663 x 0.524)
atomic mass = 2.856 +49.639 + 45.742 + 108.979
atomic mass = 207.216 u
Answer:
electroluminescence is a production of light by the flow of electrons, as within certain crystals. An example is at most resataurants with a bright sign that either says open or closed.
Explanation:
1mol—44g/mol
0.10mol—x
x=0.10*44
x=4.4 g
Answer:
317.7778 g
Explanation:
Given data:
Flour required for 18 cup cakes = 260 g
Flour required for 22 cup cakes = ?
Solution:
We will calculate the flour required for 1 cup cake.
260 g /18 = 14.4444 g
Fluor required for 22 cupcakes,
22× 14.4444 g = 317.7778 g
In short,
22 cupcake/18 cup cake×260 g = 317.7778 g
Answer:
Explanation:
Exothermic: the surrounds feel warmer. A wood fire stove is a good example of an exothermic reaction. You can feel the heat on your hands. It's exothermic.
Endothermic is exactly the opposite. The reaction takes place, but the heat comes from the surroundings. When you touch something that goes through an endothermic reaction, it feels much cooler.
This reaction, just by definition is endothermic.
