Answer:
74
Explanation:
we know,
atomic number = number of protons
so,
atomic number = 74
They help bring about chemical reactions. This is because enzymes act as catalysts, lowering the activation energy required for a chemical reaction to initiate. It is in this way that they bring about chemical reactions.
Answer:
CaCO3 -> CaO + CO2
Explanation:
Woahhhh, did you balance it yourself just then?
Answer: True.
Explanation.
The group 7A is actually named group 17.
That group is the halogens: F, Cl, Br, I, At, and Ts (Ts is one of the last elements discovered).
Those elements have 7 valence electrons (notice that it is the same number as the second digit in 17).
The atoms with 7 valence electrons will "easily" gain one electron to get the configuration of the next noble gas (8 valence electrons). That is why these elements gain electrons to form ions.
When atoms gain electrons form anions (negative ions). For example: F(-), Cl(-), Br(-), I(-).
Aluminium Hydroxide on decomposition produces Al₂O₃ and Water vapors.
<span> 2 Al(OH)</span>₃ → Al₂O₃ + 3 H₂O
According to equation at STP,
67.2 L (3 moles) of H₂O is produced by = 78 g of Al(OH)₃
So,
65.0 L of H₂O will be produced by = X g of Al(OH)₃
Solving for X,
X = (65.0 L × 78 g) ÷ 67.2 L
X =
75.44 g of Al(OH)₂Result: 75.44 g of Al(OH)₂ is needed to decompose in order to produce 65.0 L of water at STP in stoichiometry