Freshly cut sodium has a metallic sheen. Within a few minutes, water in the air causes a layer of sodium hydroxide to develop on exposed surfaces. The reaction is strongly exothermic and the heat transferred to the local environment ignites the hydrogen that is produced. The hydrogen burns with a bright flame.
In other words, sodium reacting with water is a chemical change and NOT a physical change. (combustion)
Chemical changes such as combustion form new substances.
2 Na + 2 H2O > 2 NaOH + H2
i am asking the same quesion it is on my chemistry homework and i dont know the answer!!
The dissolving of sodium hydroxide in water is a physical change because no new substances are formed. Sodium hydroxide breaks down into its ions in the water, but its chemical composition remains the same.
No, it is simply the water dissolving the sodium acetate, which is a physical change. There is a physical change when you introduce a seed crystal to the sodium acetate as the bonds in the chemical become different to form a solid. By adding water, you are just dissolving it and then allowing it to become supersaturated through heating.
It is a physical change because no new substances are formed during the process of dissolving. Sodium hydroxide dissociates into its ions in water, but the chemical composition of the sodium hydroxide remains the same.
It is a chemical reaction for not only has the state changed of NaOH, but the identity of the substances have also changed.NaOH + H2O --> Na+ + OH-The "H2O" is not a reactant. It's actually supposed to go over the arrow. Sorry.Nonetheless, the dissolution of NaOH will increase the Hydroxide concentration, thus making it more basic. It will not change the identity of H2O.
It is a chemical reaction - a chemical change.
This is a chemical reaction, a chemical change.
i am asking the same quesion it is on my chemistry homework and i dont know the answer!!
Its a chemical change. its like an acid reacting with a base to form salt and water.
it would be a chemical property because is changes
The dissolution of sodium chloride in water is considered a physical change because no new substances are formed - the sodium chloride remains as sodium and chloride ions in the water solution.
CHEMICAL CHANGE1. Melting ice2. Boiling waterPHYSICAL CHANGE1. Baking a cake2. Burning wood
Dissolving sodium chloride in water is a physical change because the chemical composition of sodium chloride remains the same. The sodium and chloride ions are simply dispersed throughout the water, but they can still be recovered by evaporating the water.
The dissolving of sodium hydroxide in water is a physical change because no new substances are formed. Sodium hydroxide breaks down into its ions in the water, but its chemical composition remains the same.
The word equation for sodium reacting with water is: sodium + water → sodium hydroxide + hydrogen gas.
No. Sodium is an element and elements cannot be broken down (decomposed) by a chemical change.
It is a physical change. The sodium hydroxide dissolves, but it is still sodium hydroxide.