Looking at a periodic table, the metals are on the left, the transition metals in the center, the metalloids farther right, and the nonmetals at the far right of the periodic table. This means the answer is metals.
Answer:
The correct answer is Option D (diffraction).
Explanation:
- Diffraction has been known as a mechanism through which light rays divide across clusters of darkness and light rather than into the colors of the rainbow.
- That is the twisting of such an obstacle across the sun. In this case, the challenge has been the door from which the illumination moves and bends.
Other alternatives are not relevant to the specified case. So, the alternative above would be appropriate.
Answer:
Mass = 18.29 g
Explanation:
Given data:
Mass of beryllium needed = ?
Mass of nitrogen = 18.9 g
Solution:
Chemical equation:
3Be + N₂ → Be₃N₂
Number of moles of nitrogen:
Number of moles = mass/molar mass
Molar mass of nitrogen = 28 g/mol
Number of moles = 18.9 g/ 28 g/mol
Number of moles = 0.675 mol
Now we will compare the moles of nitrogen and Be.
N₂ : Be
1 : 3
0.675 : 3/1×0.675 = 2.03 mol
Mass of Be:
Mass = number of moles × molar mass
Mass = 2.03 mol × 9.01 g/mol
Mass = 18.29 g
False subscripts cannot be changed to balance chemical equations
Energy can be conserved by efficient energy use.
Answer: Option A
<u>Explanation:</u>
Energy can be transferred from one form to another, but it cannot be destroyed or created. So it can be conserved if efficiently used. Thus efficient usage of energy lead to conservation of energy. Due to conservation of energy, the forces can be renewable and non-renewable.
So, we should know how the input energy can be completely converted to another form of energy leading to efficient usage of energy without any loss. As if there is no loss, input energy will be equal to output energy leading to 100% efficiency.
