Which of them is the right symbol for the element?<br> Al(2) OR 2Al

The nonmetals helium, neon, and argon and the metals copper, silver, and gold are among only a few elements that are found in na

Fynjy0 [20]

Answer:

A pure element is a pure substance that has only one kind of atoms. If a substance is present in nature in elemental form, it means that the element is not very reactive as reactive elements exist in the form of their compounds with atoms of other elements. Element can be categorized as a metal or a non-metal based on some physical observable properties. Generally, metals are shiny lustrous solids and nonmetals are gases. Metals are good conductors of heat and electricity whereas nonmetals are not conductors.

Explanation:

Hope this helps:)

5 0

2 years ago

In a study of the conversion of methane to other fuels, a chemical engineer mixes gaseous methane and gaseous water in a 0.778 L

sergejj [24]

Answer:

the water concentration at equilibrium is

⇒ [ H2O(g) ] = 0.0510 mol/L

Explanation:

CH4(g) + H2O(g) ↔ CO(g) + 3H2(g)

∴ Kc = ( [ CO(g) ] * [ H2 ]³ ) / ( [ CH4(g) ] * [ H2O(g) ] ) = 0,30

equilibrium:

⇒ [ CO(g) ] = 0.206 mol / 0.778 L = 0.2648 mol/L

⇒ [ H2(g) ] = 0.187 mol / 0.778 L = 0.2404 mol/L

⇒ [ CH4(g) ] = 0.187 mol / 0.778 L = 0.2404 mol/L

replacing in Kc:

⇒ ((0.2648) * (0.2404)³) / ([ H2O(g) ] * 0.2404 ) = 0.30

⇒ 0.0721 [ H2O(g) ] = 3.679 E-3

⇒ [ H2O(g) ] = 0.0510 mol/L

7 0

3 years ago

The combustion of ethene in the presence of excess oxygen yields carbon dioxide and water: c2h4 (g) + 3o2 (g) → 2co2 (g) + 2h2o

meriva

Answer:

$\boxed{-267.5}$

Explanation:

You can calculate the entropy change of a reaction by using the standard molar entropies of reactants and products.

The formula is

$\Delta_{r} S^{\circ} = \sum_n {nS_{\text{products}}^{\circ} - \sum_{m} {mS_{\text{reactants}}^{\circ}}}$

The equation for the reaction is

C₂H₄(g) + 3O₂(g) ⟶ 2CO₂(g) + 2H₂O(ℓ)

ΔS°/J·K⁻¹mol⁻¹ 219.5 205.0 213.6 69.9

$\Delta_{r} S^{\circ} = (2\times213.6 + 2\times69.9) - (1\times219.5 + 3\times205.0)\\\\= 567.0 - 834.5 = \boxed{-267.5 \text{ J}\cdot\text{K}^{-1} \text{mol}^{-1}}$

3 0

3 years ago

Name the element described in each of the following:

borishaifa [10]

Alkaline earth metal whose cation isoelectric with Kr is strontium (Sr).

What is Alkaline earth metal?

Six chemical elements from group 2 of the periodic chart make up the alkaline earth metals. They are boron (R), barium (Ba), calcium (Ca), strontium (Sr), magnesium (Mg), beryllium (Be), and radium (Ra). The elements share many characteristics, including being glossy, silvery-white, moderately reactive metals at standard pressure and temperature.

They share a full outer s-orbital structurally, meaning that this orbital includes all two of its electrons, which the alkaline earth metals rapidly lose to form cations with a charge of +2 and an oxidation state of +2.

All of the identified alkaline earth metals are found in nature, albeit radium is not a primordial element but only appears as part of the decay chain of uranium and thorium.

The chemical element strontium has the atomic number 38 and the symbol Sr. Strontium is a soft, silver-white, yellowish metallic element that is an alkaline earth metal and has a strong reactivity to chemicals. When the metal is exposed to air, a thick layer of dark oxide forms. Similar to its two vertical neighbors in the periodic table, barium and calcium, strontium exhibits physical and chemical characteristics. It is mostly obtained from the minerals celestine and strontianite, where it is found naturally.

To learn more about Strontium click on the link below:

brainly.com/question/19904990

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8 0

1 year ago

_______ in the mountains melts into water.<br>

Zigmanuir [339]

Answer:

Ice

Explanation:

When ice melts it makes water

8 0

2 years ago

Which of them is the right symbol for the element? Al(2) OR 2Al