Answer:
A. Peroxide breaking down into water and oxygen
Explanation:
Generally when it comes to changes, there are physical and chemical changes. In physical changes, there are no new substances been formed, however in chemical change new substances are formed.
A. Peroxide breaking down into water and oxygen
This is a chemical change.
B
. Bubbles forming when a pot of water is heated
This is a physical change
C. A pair of jeans soaked in water drying after hanging outside
This is a physical change
D
. A block of ice decreasing in size due to a change in temperature
This is a physical change.
Only option A is different from the rest,hence this is the answer.
Percent composition by mass is calculated (mass of element within compound)/(mass of compound)*100. The lower the total molar mass of the compound, the greater the percent composition of sulfur. In this case, MgS would be that compound, since Mg has the lowest molar mass of the four elements bonded to S.
<span>When water decomposes into oxygen and hydrogen, the mass "Remains Constant" as according to Law of Conservation of mass, mass can neither be created not destroyed,.
In short, Your Answer would be Option A
Hope this helps!</span>
Molar mass Na = 23.0 g/mol
1 mol ---- 23.0 g
n mol ---- 69 g
n = 69 / 23.0
n = 3.0 moles
1 mole -------- 6.02x10²³ molecules
3.0 moles ---- ?
3.0 * 6.02x10²³ / 1
= 1.806x10²⁴ molecules
hope this helps!
Answer:
the nucleus is the center of the atom, made up of protons and neutrons, without the nucleus you'd just have a bunch of electrons floating around; the nucleus is positively charged
protons are the positively charged particles that sit within the nucleus
neutrons are particles of no charge that sit within the nucleus, and because they have no charge, they do not cancel out the positive charge of the protons, making the nucleus positive
electrons are negatively charged particles that float around the nucleus in an area known as the electron cloud, they orbit around the nucleus because they are attracted to the positive charge of the nucleus (caused by the protons), with charges, opposites attract
Explanation:
