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notsponge [240]
3 years ago
15

Which is an element? A: H20 B: NaCl C: Mg D: CO

Chemistry
2 answers:
xz_007 [3.2K]3 years ago
4 0
D is the answer. The others are compounds not single elements
Talja [164]3 years ago
3 0
The answer is option D "CO." Co also known as Cobalt is the 27th element on the periotic table. It was discovered in <span>1735, it's boiling point is 3200 k.</span>

Atomic mass: 58.9332
Protons: 27
Neutrons: 32
Electrons: 27

Hope this helps!

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Answer:

The steps that must be long to obtain separately the components (to the substances) of a mixture of water, salt and sand, are respectively: A) filtration and siphoning B) decanting and siphoning C) simple filtration and distillation D) collection and decantation.

Simple filtration and Siphoning is the method. When an insoluble solid is present in a liquid. Filtration is the ideal method of separation,The sand is filtered by the filtered paper as water is allowed to pass through the filter paper into a beaker where the funnel which hold the filter paper emptied into.

Water molecules is Siphoned, pull by force of gravity through the sand, past  the filter paper to emerge as clean in the beaker below.

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True or False: Natural selection doesn't happen anymore.
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What are the steps to evaporation but without heat just evaporation steps to follow
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First, the sun shines liquid (ocean) Next, the water evaporates 
8 0
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A 6.55 g sample of aniline (c6h5nh2, molar mass = 93.13 g/mol) was combusted in a bomb calorimeter. if the temperature rose by 3
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4 0
4 years ago
Hydrogen gas (a potential future fuel) can be formed by the reaction of methane with water according to the following equation:
dem82 [27]

Answer:

The percent yield of the reaction is 62.05 %

Explanation:

Step 1: Data given

Volume of methane = 25.5 L

Pressure of methane = 732 torr

Temperature = 25.0 °C = 298 K

Volume of water vapor = 22.0 L

Pressure of H2O = 704 torr

Temperature = 125 °C

The reaction produces 26.0 L of hydrogen gas measured at STP

Step 2: The balanced equation

CH4(g) + H2O(g) → CO(g) + 3H2(g)

Step 3: Calculate moles methane

p*V = n*R*T

⇒with p = the pressure of methane = 0.963158 atm

⇒with V = the volume of methane = 25.5 L

⇒with n = the moles of methane = TO BE DETERMINED

⇒with R = the gas constant = 0.08206 L*atm/mol*K

⇒with T = the temperature = 298 K

n = (p*V) / (R*T)

n = (0.963158 * 25.5 ) / ( 0.08206 * 298)

n = 1.0044 moles

Step 4: Calculate moles H2O

p*V = n*R*T

⇒with p = the pressure of methane = 0.926316 atm

⇒with V = the volume of methane = 22.0 L

⇒with n = the moles of methane = TO BE DETERMINED

⇒with R = the gas constant = 0.08206 L*atm/mol*K

⇒with T = the temperature = 398 K

n = (p*V) / (R*T)

n = (0.926316 * 22.0) / (0.08206 * 398)

n = 0.624 moles

Step 5: Calculate the limiting reactant

For 1 mol methane we need 1 mol H2O to produce 1 mol CO and 3 moles H2

H2O is the limiting reactant. It will completely be consumed (0.624 moles).

Methane is in excess. There will react 0.624 moles. There will remain 1.0044 - 0.624 moles = 0.3804 moles methane

Step 6: Calculate moles hydrogen gas

For 1 mol methane we need 1 mol H2O to produce 1 mol CO and 3 moles H2

For 0.624 moles H2O we'll have 3*0.624 = 1.872 moles

Step 9: Calculate volume of H2 at STP

1.0 mol at STP has a volume of 22.4 L

1.872 moles has a volume of 1.872 * 22.4 = 41.9 L

Step 10: Calculate the percent yield of the reaction

% yield = (actual yield / theoretical yield) * 100 %

% yield = ( 26.0 L / 41.9 L) *100 %

% yield = 62.05 %

The percent yield of the reaction is 62.05 %

6 0
3 years ago
Read 2 more answers
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