Answer: The mass of electrons is mostly ignored because electrons are extremely small compared to neutrons and protons.
Explanation: A proton is about 1,836 times the size of an electron.
On the periodic table, the atomic number for each element can be found. This number is found by measuring the weight of 6.02 x 10^23 atoms of the element in grams. Electrons aren't ignored when finding exact math, but for the sake of simplification high school teachers will generally have you only count the number of protons and neutrons when calculating the mass of atoms.
Another name for a mesh screen is a sieve.
I believe this topic is quantitative chemistry but I need the equation to work this out sorry
Answer:
Identify each equation as a composition reaction, a decomposition reaction, or neither.
Fe2O3 + 3 SO3 → Fe2(SO4)3
NaCl + AgNO3 → AgCl + NaNO3
(NH4)2Cr2O7 → Cr2O3 + 4 H2O + N2
Solution
In this equation, two substances combine to make a single substance. This is a composition reaction.
Two different substances react to make two new substances. This does not fit the definition of either a composition reaction or a decomposition reaction, so it is neither. In fact, you may recognize this as a double-replacement reaction.
A single substance reacts to make multiple substances. This is a decomposition reaction.
Test Yourself
Identify the equation as a composition reaction, a decomposition reaction, or neither.
C3H8 → C3H4 + 2 H2
Explanation:
I hope I help :)))
Because atoms are the small and can't be seen by your eyes. It is so small that scientists need to use a model. A model help scientists study things. So, scientists needs to study atoms using models.