Answer:
a solution color becoming less intense due to dilution- is not an evidence of a chemical reaction
bubbles (gas formation) - evidence of a chemical reaction
explosion or fire - evidence of a chemical reaction
changes in color- evidence of a chemical reaction
precipitation- evidence of a chemical reaction
changes in temperature - evidence of a chemical reaction
a solid liquifying - is not an evidence of a chemical reaction
solution colors mixing - is not an evidence of a chemical reaction
Explanation:
A chemical change is not easily reversible and yields new substances. It is often accompanied by a loss or gain of heat.
In the answer section, i have shown some evidences that lead us to conclude that a chemical reaction has taken place. The occurrence of a chemical change often goes with the formation of new substances as earlier stated and any of these signs may accompany the process.
For instance, when a metal is dropped in dilute acid solution, bubble of hydrogen gas indicates that a chemical reaction has taken place.
Answer:
The ratio of the mass ratio of S to O; in SO, to the mass ratio of S to O; in SO₂, is 2:1
Explanation:
According to the consideration, let us first find the ratio of S and O in both the compounds
For SO:
Let us express it as

For SO₂,
Due to two oxygen atoms in the molecule, the mass of oxygen will be taken two times

Let us express it as

Now, for the ratio of both the above-calculated ratios,

The required ratio is 2:1
Answer:
The correct option here is the first option
Explanation:
Covalent bond is the bond that involves the sharing of electrons between the participating atoms. The electrons (in the outermost shells of the atoms) that are involved this sharing are called the "shared pair" while those electrons (in the outermost shells of the atoms) that are not involved in this sharing are called the "lone pair". Bonding eventually leads to each of the participating atoms achieving it's octet configuration.
Carbon will bind covalently with fluorine (to form carbon tetrafluoride) with each of the electrons on the outermost shell of the carbon been shared covalently with fluorine atoms (that also requires just one electron to achieve it's octet configuration). Thus, at the end, we would have one carbon atom being covalently linked to four flourine atoms.
Answer:
Heterogeneous mixture
Explanation:
A homogeneous mixture is defined as a mixture in which the constituents of the mixture are uniformly distributed. A typical example of a homogeneous mixture is when a salt is dissolved in water.
A heterogeneous mixture refers to a kind of mixture whereby the composition of the mixture is not uniform. A typically example of a heterogeneous mixture is non-homogenized milk.
Since non-homogenized milk is not homogeneous, the cream rises to the top and separates from the rest of the mixture because the emulsion has not been stabilized. However, homogenized milk is just milk whose emulsion has been stabilized the cream does not separate when left to stand.
Ok so I’m going to break it up so it’s a bit easier to read through:
The colours are from the different rocks and minerals that make up the sand.
The little fragments of rock come from for example surrounding mountains.
It could also because sand is simply the product from erosion of the rocks rubbing each other under the action of the waves.
So if the bottom of the ocean is made of black lava for example in Hawaii, there’s a good chance of the sand being black.
In California, the sand usually looks white because it has minerals like quartz and pieces of shell that are made of calcium carbonate.
Hope this helps :)