Can easily be cut with a sharp knife?
Solution. Since the sharp-edged knife makes lesser contact with the fruits to be cut, thus the pressure exerted by it on the fruit is very large. Because of this large pressure, fruits are easily cut with a sharp knife.
Can be easily cut with a knife?
Sodium is an alkali metal and is so soft that it can be easily cut by knife.
Which metal Cannot be easily cut with a knife?
Answer. The hardest metal is chromium, which cannot cut with a knife.
Can cesium cut with knife?
Hi! Elements belonging to Group 1 of the periodic table are known as Alkali metals. They are Lithium, Sodium, Potassium, Rubidium, Caesium and Francium. These are soft metals and therefore, can be cut with a knife.
Can a knife cut through metal?
A knife or a scalpel cannot cut through a metal safe. Some metal safes can be cut open with a sawzall or a cutting torch and you can break some safes open with a good sledge hammer.
What is the most active metal on earth?
Cesium
Do alkali metals react with water?
Alkali metals react with water to produce heat, hydrogen gas, and the corresponding metal hydroxide. The heat produced by this reaction may ignite the hydrogen or the metal itself, resulting in a fire or an explosion. The heavier alkali metals will react more violently with water.
What happens if sodium metal is dropped in water?
(i) When sodium metal is dropped in water, hydrogen gas is evolved which catches fire. (ii) When sodium metal is heated in a free supply of air, sodium peroxide (Na2O2) along with small amount of sodium oxide is formed. (iii) When sodium peroxide is dissolved in water, hydrogen peroxide is produced.
Why sodium can be easily cut with a knife?
Sodium has one electron in its valence shell. The force of attraction binding the metal ions with electrons, that means, metallic bond is weaker when compared to the other metals. Therefore, sodium is soft metal and can be cut with a knife.
Is sodium soft enough to be cut with a knife?
Sodium and potassium are soft metals. So an ordinary knife and a little pressure is enough to cut them.
Why sodium and potassium can be easily cut with a knife?
Terefore, they have weak metallic bonding between the atoms. Due to the presence of weak metallic bonding alkali metals are soft and can be cut with a knife. Here potassium has larger atomic size than sodium. Hence, the ionization enthalpy of potassium is less than sodium.
Is rubidium easy to cut?
Rubidium is a silvery-white, soft metal (Fig. 1), and it is one of the most reactive of all the known elements. In fact, alkali metals are so soft they can be easily cut with a knife, but the exposed surface will tarnish and oxidize quickly in air.
Is Caesium easy to cut?
Caesium (cesium in USA) is very soft and easily cut. The resulting surface is bright and shiny. However, this surface soon tarnishes because of reaction with oxygen and moisture from the air.
Is rubidium toxic?
Moderately toxic by ingestion. If rubidium ignites, it will cause thermal burns. Rubidium readily reacts with skin moisture to form rubidium hydroxide, which causes chemical burns of eyes and skin.
Is rubidium harmful to humans?
Rubidium is not particularly harmful to humans, and once in the body its ions are rapidly excreted in sweat and urine.
What happens if you eat rubidium?
Rubidium compounds are not very dangerous in the human body; however, if a person gets too much from eating, they could get sick because it acts like other alkali metal ions such as sodium ions in sodium chloride.
Why is rubidium not used in schools?
Why is the reason behind rubidium not being used in schools? Rubidium is a soft, silvery-white metallic element of the alkali metal group, with a standard atomic weight of 85.4678. Elemental rubidium is highly reactive, with properties similar to those of other alkali metals, including rapid oxidation in air.
Who found rubidium?
Robert Bunsen
What happens when Rubidium is exposed to air?
Rubidium ignites spontaneously when exposed to air and reacts violently with water, releasing hydrogen, which immediately bursts into flames. According to Encyclopedia Britannica, rubidium must be kept in mineral oil or in an inert gas atmosphere.