Questions tagged [alkali-metals]
For questions about the alkali metals (group 1), their compounds, and their physical and chemical properties. For questions specifically about hydrogen, use tag [hydrogen] instead.
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Why is Li easiest to oxidise among the alkali metals despite having the greatest ionization energy 1 in the group? [closed]
If we use the magnitude of the IE1 as an indicator of ease of oxidation, Li is the most difficult of the alkali metals to oxidise. On the other hand, if E0redn (standard reduction electrode potential) ...
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How does sodium react with methanol?
Strong acids of $\ce{AH}$ type readily dissociate to its constituent ions (considering the solvent is water): $\ce{A-}$ and $\ce{H+}$. But the mechanism of the reaction between sodium metal and ...
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Why do H and Li bond so differently with a hydroxide?
I am sure I am asking a very basic question but before coming here, I have made multiple attempts to find an answer elsewhere. Or maybe I am simply asking the wrong question, in some sense. If someone ...
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Combustion of Sodium (Na) Metal in presence of Excess Air [duplicate]
There was a question which I was recently solving regarding the products formed after combustion of Sodium Metal in presence of Excess Air.
The given answers were Na2O2 (sodium peroxide) and Na2O (...
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Dissolution of portlandite, calcite/CaCo3 phase and C-S-H due to high pH
I would like to ask about the possibility of the partial dissolution, over curing time, of portlandite, CaCo3 and C-S-H phases due to high pH (12.5 - 13) of the lime-clay-water systems (lime-...
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What kind of solution is formed when alkali metals are dissolved at high concentration in liquid ammonia?
When an alkali metal is dissolved in liquid ammonia, it results in the formation of a deep blue coloured solution. $$\ce{M + (x + y) NH3 -> M+(NH3)_x + e^-(NH3)_y}$$
The ammoniated electrons absorb ...
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Is it possible that the chemical composition of Greek fire could have been an alkali metal?
"Greek fire" was an ancient weapon used by the Greeks noted as being inextinguishable by water. The chemical composition of this weapon has been debated in the historical scholarship; due to ...
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Why does the pH of very strong NaOH solutions not make sense? [duplicate]
I'm wondering why the pH of extreme alkaline solutions, such as the case with $\pu{10 M}$ $\ce{NaOH}$ does not make practical sense and I'm wondering why this is the case? Refer to my calculations ...
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What is the mechanism of sodium reacting with water vapor?
We all know that
$$\ce{2Na +2H2O(g)->2NaOH +H2}$$
The question is:
What is the mechanism (not the reason that sodium is more 'electropositive' or more reactive than hydrogen, as in this question; ...
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Comparison between Atomic Spectrum of Hydrogen and Alkali Metals
I posted a question on Chemistry Stack Exchange a while back. It was related to the naming of atomic orbitals. One of the answers to it mentioned a research experiment. The link to the question is ...
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Permitted composition of lithium oxometallate in lithium-ion battery and its influence on ion transfer
The following scheme describes the overall reaction that takes place in a Li-ion battery:
$$
\begin{align}
\ce{Li_{$y$}C6 &-> $y$ Li+ + $y$ e- + C6} &\quad &\text{(anode)} \tag{R1}\\
\...
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Is sodium superoxide more abundant than sodium oxide?
Reference(NCERT book of India);
My professor has taught me that $\ce{Na2O}$ and $\ce{Na2O2}$ are the most common oxides of sodium, but in my reference book it is written that they are $\ce{NaO2}$ and ...
user120451
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Why does Cesium have a higher Boiling point compared to Rb? [closed]
i know BP should decreese down the group as Cohesive energy decreeses down the group but i found out that cs>Rb in terms of B.P..
so what other factor is affecting this?
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Why is there a large increase in volume when an alkali metal is dissolved in liquid ammonia?
My teacher said unexplainedly that when alkali metals dissolves in liquid ammonia, there is a large increase in the volume. I found a paper that confirms this fact [1]:
In the course of recent ...
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Why is reaction of Li less vigorous than that of Na although the former has a more negative SRP value?
My textbooks says:
It may be noted that although lithium has most negative E0 value (Table 10.1), its reaction with water is less vigorous than that of sodium which has the least negative E0 value ...
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Will Lithium displace a sodium salt?
This question is based on a discrepancy I have observed in my limited knowledge about the reactivity and electrochemical series.
In the reactivity series it is mentioned that Na>Li in reactivity ...
user121185
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lowest melting point of alkali salts [closed]
I want to make the alkali metals sodium and potassium through electrolysis of molten salts. However, I only have the ability to heat stuff up to about 260 degrees Celsius.
What would be the lowest ...
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Why are hydrated lithium ions' radii larger than hydrated sodium ions' radii?
Why are hydrated lithium ions' radii larger than hydrated sodium ions' radii i.e. $r_\ce{Li+(aq)}>r_\ce{Na+(aq)}$?
If ionic radii increase down the group i.e. $r_\ce{Li+}<r_\ce{Na+}<r_\ce{K+}$...
user119959
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Mixing hydrogen peroxide and sodium hydroxide doesn't lead to sodium peroxide anymore [closed]
I've been using same bottle of hydrogen peroxide and same bottle of 50 % of sodium hydroxide to make sodium peroxide for a month now. You could see the presence of sodium peroxide in the solution ...
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Stability of Lithium hydride over Sodium hydride
Why is LiH more stable to heat compared to NaH?
The lithium cation is harder than the sodium cation. The hydride ion is soft. Hence, I would assume that LiH would be more stable compared to NaH, owing ...
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Cobalt glass colour of potassium as
Question:
Cobalt glass colour of potassium as:
A) Crimson red
B) Lilac
C) Apple green
D) Brick red
I thought option B as true because on flame test, potassium gives lilac colour. But the given ...
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What is the colour of cesium?
I am confused with the color of cesium. Some websites and books say that it is a silvery white metal, and some say it has a golden colour, and some say it has a silvery golden colour.
Among these ...
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Ease of reaction of hydrogen with alkali and alkaline earth metals
The ease of reaction of group 1 metals with hydrogen decreases as we
go down the group.
But why lithium requires high temperature than sodium, potassium and
rubidium?
What is exactly "ease of ...
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436
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Does lithium form ionic hydride? [duplicate]
It is stated in my chemistry textbook that lithium indeed forms lithium hydrides. However, significant covalent characters could be found in lithium hydrides (like least reactivity).
But in some other ...
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Metal oxide formation minimum temperature?
Is there such thing as minimum temperature for creation of metal oxide?
Let's say a highly reactive metal, lithium, comes into contact with solid oxygen at a cryogenic temperature of 20 Kelvin, would ...
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Why does fcc lithium melt with increased pressure?
According to the phase diagram of lithium given here, the fcc phase formed at moderately high pressure melts at decreasing temperature upon adding more pressure, an effect better known with the ...
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Why is it that not all metals produce hydroxides when reacting with water? [duplicate]
I was taught, as a rule, that:
metals + water $\rightarrow$ metal hydroxide + hydrogen gas
$$\text{Na} + \text{H}_2\text{O} \rightarrow \text{NaOH} + \text{H}_2$$
However:
$$3\text{Fe} + 4\text{H}...
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Lithium Oxide Colour
According to Chemistry LibreText:
Lithium is the lightest of all metals and is named from the Greek work for stone (lithos). It is the first member of the Alkali Metal family. It is less dense than ...
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Can sodium metal deprotonate terminal hydrogen atom from propyne to form propynide?
I've read that sodium metal is used to form ethynides but for forming propynide, they have used $\ce{NaNH2}$. Is there some reason for not using sodium metal for propynides as well?
Source: Chemistry ...
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Do positive results of a lead paint testing kit imply that a dipped door is now toxic?
We have had some 1930's doors dipped in a caustic solution to remove the paint.
Before dipping, we found that a layer of yellow paint contained lead. It tested positive with: https://www.amazon.com/...
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Ionic mobilities and conductivities of lithium and potassium cations in acetonitrile–propylene carbonate solution
Recently I calculated the ionic mobility and molar ionic conductivity values for $\ce{Li+}$ and $\ce{K+}$ cations in an acetonitrile–propylene carbonate binary mix solution (8:2 molar fraction ratio).
...
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Why does conductivity of a solution of sodium in liquid ammonia decrease with a decrease in temperature?
What happens to the conductivity when a solution of sodium in liquid ammonia at $\pu{-33^{\circ}C}$ (Boiling point of ammonia) is further cooled?
I expected the solution to behave as any other ...
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Can alkali-doped exohedral fullerene molecules show superconducivity?
Alkali doped fullerenes are one of the few organic materials that show superconductivity. However, when attaching a new molecular system to a fullerene doped with an alkali metal, will it still show ...
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Why is potassium less dense than sodium?
Potassium has a density of $\pu{0.86g/cm3}$ and sodium has a density of $\pu{0.97g/cm3}$,even though potassium is below sodium and one might expect the alkali metals to exhibit monotonously increasing ...
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What determines the consistency of hydrogen foam when reacting aluminium with sodium hydroxide solution?
I was using $\ce{NaOH}$ solution to remove hardened grease from my stove burners, and it began to generate a lot of bubbles, some of which merged into a big bubble and erupted into the surface, but ...
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Significance of p functions in compounds of the lighter alkaline and alkaline earth metals [closed]
It is often said that lithium follows the duet rule instead of the octet rule, unlike the more "usual" main-group elements.
My question is the following:
Does this hold for $\ce{Be, Na}$ and ...
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Do all metal nitrates give nitrogen dioxide on decomposition?
Some metal nitrates decompose to give nitrites: $\ce{2MNO3 -> 2MNO2 + O2}$
whereas some metal nitrates decompose to give $\ce{NO2}$. A possible reaction is $\ce{M(NO3)2 -> MO + NO2 + O2}$
Based ...
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What is the mechanism of formation of alkali metal superoxide?
I was studying about alkali metals. I can get how oxides and peroxides are formed.
In alkali metal oxides, both of the bonds of the dioxygen molecule first undergoes homolytic cleavage, then the ...
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Color of Flame Test for Alkali Metals
Lithium is known to have the highest ionization energy among Group 1 elements. Also, characteristic colours in the flame test arise due to the excitation and de-excitation of electrons. Then why ...
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Can you get potassium by reducing KCl with lithium?
I would have said that the answer was no, because lithium is less reactive than potassium is, so you would expect the reaction to go the other way: with potassium and lithium chloride reacting to ...
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why do we see characteristic colors of alkali metals in oxidizing flame?
I am a high school student and I am a little confused in a topic, My confusion is that:
We know alkali metals and their salts imparts characteristic color in oxidizing flame, for example: Lithium ...
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How to read mutual solubility curves of salts with a common ion?
Came across a few graphs that represent the mutual solubility of two compounds in a solvent, for e.g., solubility of $\ce{KCl}$, and $\ce{NaCl}$ in $\ce{H2O}$.
On these particular graphs, I can see $x$...
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Wavelengths of colors emitted by alkali metals during flame test
While reading my NCERT chemistry book (Page number 300), I came across a table that mentions colors emitted by alkali metals and corresponding wavelengths. It mentions that Potassium emits a violet ...
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Why do neutral metal atoms have affinity towards electrons? [duplicate]
Since first electron affinity is almost always negative, neutral atoms of most elements (including metals) must have an affinity towards electron. But shouldn't metals want to lose electron(s) rather ...
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Why is density of chloroform greater than water?
Hydrocarbons (i.e., molecules containing carbon and hydrogen only) are generally less dense than water. Yet chloroform, which is a halogenated hydrocarbon, is more dense.
Why is this? I know water ...
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Do alkali metals react with ammonia to form hydrogen gas?
I was recently studying about s-block alkali metals and I found the following reaction:
$$\ce{\underset{alkali\\ metal}{M\phantom{_y}} + \underset{solution}{$(x +y)$ NH3} -> \underset{ammoniated\\ ...
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Hydrolysis of alkali and alkaline earth metals
Which of the following cations are not hydrolysed in aqueous solution?
1) $\ce{Mg^2+}$ 2) $\ce{Ca^2+}$ 3) $\ce{Na+}$ 4) $\ce{K+}$
I thought nothing would undergo hydrolysis, so all the options would ...
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Does Potassium Superoxide also absorb Carbon Monoxide?
Potassium Superoxide ($\ce{KO2}$) is used as an oxygen provider and carbon dioxide scrubber in life support systems
$$\ce{2KO2 + H2O -> 2KOH + O2} \\
\ce{2KOH + CO2 -> K2CO3 + H2O}$$
I ...
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If acid releases proton then how can a proton react with another proton to form hydrogen gas? [duplicate]
As we know that acid releases proton (H+ ion) when dipped in water hydrogen has a proton and electron only . To form H+ hydrogen releases 1 electron and it becomes proton. But when Acid reacts with ...
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Why does solubility of Carbonate salts of Alkali metals in water increase down the group?
Carbonate salts have a very large anion so hydration energy should dominate over lattice energy. Since hydration energy is inversely proportional to radius of ion, I would expect Lithium to release ...
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