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Fudgin [204]
3 years ago
9

What are the dark spots on the sun called

Chemistry
1 answer:
kap26 [50]3 years ago
3 0

Answer:

Sunspots

Explanation:

Hope this helped!! :)

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45.7 grams of calcium chloride reacts with an excess of aluminum oxide. How many grams of aluminum chloride will be produced
damaskus [11]
Molar mass (CaCl2) = 40.1 +2*35.5 = 111.1 g/mol
Molar mass (AlCl3) = 27.0 +3*35.5= 133.5 g/ mol

                                               
3CaCl2+Al2O3 -------->3CaO +2AlCl3
mole from reaction              3 mol                                              2 mol
mass from reaction         3mol* 111.1g/mol                             2 mol*133.5g/mol
                                               333.3 g                                            267.0 g
mass from problem              45.7 g                                               x g

Proportion:
  333.3 g  CaCl2  -------   267.0 g AlCl3
  45.7 g   CaCl2   --------   x g    AlCl3

x=45.7*267.0/333.3= 36.6 g AlCl3
5 0
3 years ago
If you burn 55.6 g of hydrogen and produce 497 g of water, how much oxygen reacted?
tester [92]

Answer:

441.28 g Oxygen

Explanation:

  • The combustion of hydrogen gives water as the product.
  • The equation for the reaction is;

2H₂(g) + O₂(g) → 2H₂O(l)

Mass of hydrogen = 55.6 g

Number of moles of hydrogen

Moles = Mass/Molar mass

          = 55.6 g ÷ 2.016 g/mol

          = 27.8 moles

The mole ratio of Hydrogen to Oxygen is 2:1

Therefore;

Number of moles of oxygen = 27.5794 moles ÷ 2

                                               = 13.790 moles

Mass of oxygen gas will therefore be;

Mass = Number of moles × Molar mass

Molar mass of oxygen gas is 32 g/mol

Mass = 13.790 moles × 32 g/mol

<h3>          = 441.28 g</h3><h3>Alternatively:</h3>

Mass of hydrogen + mass of oxygen = Mass of water

Therefore;

Mass of oxygen = Mass of water - mass of hydrogen

                          = 497 g - 55.6 g

<h3>                           = 441.4 g </h3>
6 0
4 years ago
Read 2 more answers
Calculate the electrical energy per gram of anode material for the following reaction at 298 K:
solmaris [256]

43.8 kJ

<h3>Explanation</h3>

There are two electrodes in a voltaic cell. Which one is the anode?

The lithium atom used to have no oxygen atoms when it was on the reactant side. It gains two oxygen atoms after the reaction. It has gained more oxygen atoms than the manganese atom. Gaining oxygen is oxidation. As a result, lithium is being oxidized.

Oxidation takes place at the anode of a cell. Therefore, the anode of this cell is made of lithium.

Lithium has an atomic mass of 6.94. Each gram of Li would contain 1/6.94 = 0.144 moles of Li atoms. Each Li atom loses one electron in this cell. Therefore, the number of electron transferred, <em>n</em>, equals 0.144 moles for each gram of the anode.

Let w_\text{max} represents the electrical energy produced.

w_\text{max} = n \cdot F \cdot E_\text{cell}, where

  • <em>n</em> is the <em>number of moles</em> electrons transferred,
  • <em>F</em> is the Faraday's constant,
  • <em>E</em>_\text{cell} is the cell potential,

<em>n </em>= 0.144 mol, as shown above, and

<em>F </em>= 96.486 kJ / (\text{V} \cdot \text{mol} \; \text{e}^{-}).

Therefore,

w_\text{max} = n \cdot F \cdot E\\\phantom{w_\text{max}} = 0.144 \times 96.486 \times 3.15 \\\phantom{w_\text{max}} = 43.8 \; \text{kJ}.

3 0
4 years ago
The molar mass of H2O is 18.01 g/mol. The molar mass of O2is 32.00 g/mol. What mass of H2O,in grams, must react to produce 50.00
N76 [4]
Answer is: mass of water is 56.28 grams.
Chemical reaction: 2H₂O → 2H₂ + O₂.
m(O₂) = 50.00 g.
n(O₂) = m(O₂) ÷ M(O₂).
n(O₂) = 50 g ÷ 32 g/mol.
n(O₂) = 1.5625 mol.
From chemical reaction: n(O₂) : n(H₂O) = 1 : 2.
n(H₂O) = 2 · 1.5625 mol.
n(H₂O) = 3.125 mol.
m(H₂O) = n(H₂O) · M(H₂O).
m(H₂O) = 3.125 mol · 18.01 g/mol.
m(H₂O) = 56.28 g.
7 0
3 years ago
Read 2 more answers
You water three sunflower plants with salt water. Each plant receives a different concentration of salt solutions. A fourth plan
quester [9]

Answer:

Please please please mark me brainlest!

Explanation:

IV: salt solution

DV: Hight of plants

Control: the fourth plant

Independent Variable: what it's watered with (regular water or salt water as well as the concentration of salt water)

Dependent Variable: Height

Control: the type of plant (sunflower) Hope this helps you! Ask me anything if you have any quistions!

8 0
4 years ago
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