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2 years ago

How many atoms are in 5.2 moles of Na ?

1 answer:

8 0

One mole of a substance is defined by Avogadro as consisting of 6.022 x 1023 atoms. This is Avogadro's number. To calculate the number of atoms in two moles of sodium, use dimensional analysis. 2.0 moles Na x 6.022⋅1023g1mol=1.20⋅1024 atoms of Na

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Inorganic compounds contain carbon true or false

Sladkaya [172]

Hello,

The correct answer would be:

True.

Inorganic compounds contain: carbon monoxide, carbon dioxide, carbonates,cyanides, cyanates, carbides, and thiocyanates

Mark brainliest if helped!

8 0

3 years ago

Read 2 more answers

Consider the intermediate chemical reactions. 2 equations. First: upper C a (s) plus upper C upper O subscript 2 (g) plus one ha

DochEvi [55]

Answer: When the enthalpy of this overall chemical equation is calculated, the enthalpy of the second intermediate equation is halved and has its sign changed.

Explanation:

Hess’s law of constant heat summation states that the amount of heat absorbed or evolved in a given chemical equation remains the same whether the process occurs in one step or several steps.

According to this law, the chemical equation is treated as ordinary algebraic expressions and can be added or subtracted to yield the required equation. This means that the enthalpy change of the overall reaction is equal to the sum of the enthalpy changes of the intermediate reactions.

The overall chemical reaction follows:

$CaO(s)+CO_2\rightarrow CaCO_3(s)$ $\Delta H^o_{rxn}=?$

The intermediate balanced chemical reaction are:

(1) $Ca(s)+CO_2(g)+\frac{1}{2}O_2(g)\rightarrow CaCO_3(s)$ $\Delta H_1=-812.8kJ$

(2) $2Ca(s)+O_2(g)\rightarrow 2CaO(s)$ $\Delta H_2=-1269kJ$

The expression for enthalpy of the reaction follows:

$\Delta H^o_{rxn}=[1\times (\Delta H_1)]+[\frac{1}{2}\times (-\Delta H_2)]$

Hence, when the enthalpy of this overall chemical equation is calculated, the enthalpy of the second intermediate equation is halved and has its sign changed.

3 0

3 years ago

A drought is best defined as

Lapatulllka [165]

A drought is a period of drier-than-normal conditions that results in water-related problems. When rainfall is less than normal for several weeks, months, or years, the flow of streams and rivers declines, water levels in lakes and reservoirs fall, and the depth to water in wells increases.

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3 years ago

What are the 7 methods of separating mixtures?

Gennadij [26K]

Methods Of Separating Mixtures

Handpicking.

Threshing.

Winnowing.

Sieving.

Evaporation.

Distillation.

Filtration or Sedimentation.

Separating Funnel.

3 0

3 years ago

Read 2 more answers

What is the weight of oxygen in 50gwater

8_murik_8 [283]

To compute the required mass of the element to form the given molecules, we'll use the general formula shown below:

{eq}\displaystyle m_1=\frac{M_1}{M_2}\times m_2 {/eq}, where,

{eq}M_1 {/eq} is the molecular weight of the element.

{eq}M_2 {/eq} is the molecular weight of the given molecule.

{eq}m_2 {/eq} is the mass of the given molecule.

Answer and Explanation:

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The given value is:

The value of the mass of the water molecule is {eq}m_2=\rm 50\ grams {/eq}.

The chemical reaction for the formation of water...

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Formula for Mass: Definition & Examples

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Chapter 28 / Lesson 42

52K

What is mass? Learn the mass definition and how to find the mass of an object using the mass formula. See common mass characteristics and properties.