Oxygen is a pure substance, as it is composed of only a single kind of atom. Which is the oxygen atom, it cannot be broken or degraded down any further into constituents that make up the element. In terms of both chemically and physically.
Answer: The correct option is 2.
Explanation: Heat flow is defined as the transfer of energy from hotter object to cooler object when two objects are kept together at different temperatures. As the energy remains conserved, so the heat flow will take place until the equilibrium is attained.
In the above asked question, Object A is at 40° C and Object B is at 80° C.
Object B is at higher temperature, so the heat flow will take place from Object B to Object A.
Hence, the correct option is 2.
Answer:
B
Explanation:
Dalton worked with mainly about the chemistry of atoms.
how do atoms combine to form various molecules.
—rather than the details of the physical, internal structure of atoms, although he never denied the possibility of atoms' having a substructure.
Answer:
Laboratory acids are far too dangerous to taste, but you will have swallowed some dilute weak acids. Acids have a sour taste, like vinegar, which contains ethanoic acid, and lemons, which contain citric acid. These are safe to use in food, but they can still hurt if they get into a cut or into your eyes.
Explanation:
They can safely be consumed and do not irritate the skin. However, at greater concentrations weak acids can be harmful. Acids can react violently with water and are harmful in the presence of moisture in the mouth or eyes or in proximity with other aqueous solutions.
hope that helps!
At -25 °C, methanol, whose boiling point is 64.7 °C and its melting point is -97.6 °C, is in the liquid state.
The melting point is the temperature at which a substance passes from solid to liquid. Below the melting point, a substance is in the solid state. Above the melting point, a substance is in the liquid or gas state.
The boiling point is the temperature at which a substance passes from liquid to gas. Below the boiling point, a substance is solid or liquid. Above the boiling point, a substance is in the gas state.
At -25 °C, methanol is above the melting point (-97.6 °C) and below the boiling point (64.7 °C). Thus, it is in the liquid state.
At -25 °C, methanol, whose boiling point is 64.7 °C and its melting point is -97.6 °C, is in the liquid state.
You can learn more about the melting and boiling points here: brainly.com/question/5753603?referrer=searchResults