0
A compound called calcium hydrogencarbonate is the main cause of hard water. It forms when rain falls on limestone and chalk rocks. These rocks are made of calcium carbonate, which is insoluble in water. Because rain water contains carbon dioxide, dissolved from the air, this makes it acidic. The rain water reacts with the rocks to form calcium hydrogencarbonate which is soluble. This is the white solid that ends up in our kettles.
An equation for the reaction is:
water + carbon dioxide + calcium carbonate = calcium hydrogencarbonate
H2O (l) + CO2 (g) + CaCO3 (s) = Ca(HCO3)2 (aq)
Wiki User
∙ 10y ago
Add your answer:
Earn +20 pts
What rocks dissolve?
Calcium Carbonate minerals such as gypsum, selenite and barite
What rocks dissolve fastest?
Calcium Carbonate minerals such as gypsum, selenite and barite
Will hydrocloric acid dissolve hard stone?
Not normally. Hydrochloric acid will dissolve carbonates, so marble (calcium carbonate) would be dissolved but many rocks are impervious to acids.
How does carbonate get into rocks?
There is carbon dioxide in the sea and animals die and falkl to tyhe sea bed and create carbonate in rocks
What can rain water do to rocks like limestone?
Rain water can dissolve rocks like limestone.
What rocks are dissolved by rain?
Although the carbonic acid contained in rainwater aid in the erosion of all rocks, most susceptible are the carbonate rocks such as limestone.
What rocks dissolve?
Calcium Carbonate minerals such as gypsum, selenite and barite
What rocks dissolve fastest?
Calcium Carbonate minerals such as gypsum, selenite and barite
What makes marble result?
Carbonate rocks.
Can vinegar dissolve rocks?
Calcium acetate is reasonably soluble in water, so vinegar will dissolve limestone (calcium carbonate).
What is an example of chemical weathering affecting the rocks?
Rainwater is slightly acidic and will react with the calcium carbonate found in limestone and other rocks. The resultant erosion is an example of chemical weathering.
Why carbonate rocks are most affected by acid rain?
Limestone is calcium carbonate. The reaction that occurs when acid rain damages carbonate rocks is an acid-base reaction. Hydronium ions in the rain reaction with carbonate ions in the rock to form hydrogen carbonate, which is water soluble. The overall reaction is represented by H3O+ + CO32- => H2O + HCO3-
Do all rocks react with rainwater at the same rate?
No. Rainwater is usually slightly acidic because of the carbon dioxide dissolved in it. Sometimes, it can be strongly acidic, if pollutants like sulphur dioxide and nitrogen dioxide are dissolved in it. Both weakly and strongly acidic rainwater react with some rocks, but only ones that are alkaline. Chalk is almost pure calcium carbonate and reacts fairly quickly with rainwater. Other rocks that contain calcium carbonate include limestone and marble and these react a little more slowly. But some rocks, like sandstone, are actually acidic and don't react with rainwater (though they are still physically weathered by rain). Granite also doesn't react with rainwater and it physically weathers much more slowly.
Will hydrocloric acid dissolve hard stone?
Not normally. Hydrochloric acid will dissolve carbonates, so marble (calcium carbonate) would be dissolved but many rocks are impervious to acids.
Which rock decays faster from acid rain?
Rocks containing carbonate, like limestone, dissolve fastest in acidic rain
Is rainwater weak acid that dissolves limestone and rock and creates caves?
Correct, in limestone including its meta-form marble, and gypsum; respectively calcium carbonate and calcium sulphate. The acidity comes from absorbed atmospheric carbon-dioxide. NB though: Limestone is a rock anyway, but only these two calcium compound rocks are soluble to any real extent. Dolomite (magnesium carbonate based) will dissolve but the physical nature of its deposits tends to prevent cave formation. Rainwater will also attack the felspar in granite but the process, hydrolysis, is extremely slow and does not lead to dissolutional caves in granite.
Rainwater is weak acid that dissolves limestones and rock and creates caves?
Correct, in limestone including its meta-form marble, and gypsum; respectively calcium carbonate and calcium sulphate. The acidity comes from absorbed atmospheric carbon-dioxide. NB though: Limestone is a rock anyway, but only these two calcium compound rocks are soluble to any real extent. Dolomite (magnesium carbonate based) will dissolve but the physical nature of its deposits tends to prevent cave formation. Rainwater will also attack the felspar in granite but the process, hydrolysis, is extremely slow and does not lead to dissolutional caves in granite.
