Answer:
A chemical change occurred, a gas and precipitate was produced
Explanation:
From the question , we are informed of science lab, where Cash mixes two clear liquids together in a beaker. Bubbles are produced, and a white solid forms and settles to the bottom.
In this case the change that took place is chemical change ( is one where new product are formed after two substance react) the bubbles that is produced signify the presence of gas in the product, white solid formed is reffered to as a precipitate( which is reffered to as solid that is been formed from a particular solution).
An atom of element has there subatomic particles namely, proton, electron and neutron. Here, for a neutral atom, number of proton is equal to number of electron (this is not in the case of ions), this is equal to atomic number of an atom. In an atom, nucleus contains protons and neutrons which is responsible for mass of the atom and electrons move around nucleus in fixed orbits. Thus, atomic mass of an atom is equal to sum of number of protons and neutrons.
Option (b): Proton is the particle in nucleus of an atom, whose total number is equal to atomic number of that atom.
(4) Option (b): Atoms of same element have same atomic number because mass number can be different for different isotopes of atom. Since, atomic number is equal to number of protons, thus, number of protons are same for all atoms of the same element.
(5) Option (d): Isotopes are defined as atoms of same element with same atomic number but different mass number. Thus, correct option is (d) mass numbers.
A change of one unit on the pH scale represents a change in the concentration of hydrogen ions by a factor of 10, a change in two units represents a change in the concentration of hydrogen ions by a factor of 100. Thus, small changes in pH represent large changes in the concentrations of hydrogen ions.
PV / T = P'V' / T'
V = V'
P / T = P' / T'
P = 630 mmHg
T = 100 K
P' = 1760 mmHg
T' = ?
630 / 100 = 1760 / T'
T' = 1760 / 6,3
T' = 279,36 K
T' ≈ 280 K
