Answer:
A. During the summer, Earth's rotational axis is parallel to the Sun's rotational axis.
Explanation:
Actually, though, the Earth is tilted 23.4 degrees! (A circle is 360 degrees.) This tilt is the reason that days are longer in the summer and shorter in the winter. The hemisphere that's tilted closest to the Sun has the longest, brightest days because it gets more direct light from the Sun's rays.
Plz mark me brainliest if correct :)
Given that 1 micrometer or micron (um) is equivalent by definition to 1 x 10^-6 m, this means that 1 square micron (um^2) is equivalent to (1 x 10^-6)^2 m^2, or 1 x 10^-12 m^2.
(2.60 um^2) * (1 x 10^-12 m^2 / 1 um^2) = 2.60 x 10^-12 m^2
Therefore the layer of graphene covers an area of 2.60 x 10^-12 m^2.
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Answer:
.7689 mol
15.516 g
Explanation:
Use the Ideal Gas Law, PV = nRT.
Make sure to use the correct ideal gas constant R. You can either put R in torr, or you can change the pressure to atm. I've just used the torr ideal gas constant.
481.1 torr * 29.9 L = n 62.364 LTorr/molK * 300 K
14384.89 = 18709.2n
n = <u>.7689 mol</u>
The molar mass of neon (remember that neon gas = Ne, it's not diatomic) is 20.18 g/mol from the periodic table.
.7689 mol * 20.18 g/mol = <u>15.516 g</u>
Answer:
2Mg(s) +O₂(g) → 2MgO(s)
Explanation:
Mg(s) +O₂(g) → MgO(s)
When a chemical equation is balanced, the number of atoms of each element is equal on both sides of the arrow. We usually balance O and H last.
In this case, the number of Mg atoms is equal on both sides. Thus, let's move on to balance the O atoms. On the left side, there are 2 O atoms, while there is only 1 O atom on the left side. Thus, write a '2' in front of MgO.
Mg(s) +O₂(g) → 2MgO(s)
Now, the number of Mg atoms is not equal. Write a '2' in front of Mg to balance it.
2Mg(s) +O₂(g) → 2MgO(s)
The equation is now balanced with 2 Mg atoms and 2 O atoms on each side.
Answer:
0.204 mol
Explanation:
Step 1: Write the balanced equation for the heating of calcium chloride dihydrate
CaCl₂.2H₂O ⇒ CaCl₂ + 2H₂O
Step 2: Calculate the moles of calcium chloride dihydrate
The<em> molar mass of CaCl₂.2H₂O</em> is 147.01 g/mol. The moles corresponding to 15.0 g of CaCl₂.2H₂O are:

Step 3: Establish the molar ratio of CaCl₂.2H₂O to H₂O
According to <em>the balanced equation</em>, the molar ratio of CaCl₂.2H₂O to H₂O is 1:2.
Step 4: Use the molar ratio to calculate the moles of water produced from 0.102 moles of calcium chloride dihydrate
