Answer:
a physical change does not change the composition (what it's made of) as a chemical change would.
Answer:
2Cl-
Explanation:
When a substance is reduced, it gains electrons. Because electrons are negatively charged, the substance that is reduced will have a negative charge. 2Cl- is the substance that was reduced because it became negative.
Answer:
1s2 2s2 2p6
Explanation:
The nitride ion(N^3-) is formed when nitrogen gains three electrons. Nitrogen possesses seven electrons in its orbitals and ordinarily has the electronic configuration; 1s2 2s2 2p3. However,being in group 15, nitrogen can accept three electrons to form the nitride ion and complete its octet of electrons. When this happens, three electrons are added to the nitrogen atom and the electronic configuration is now the same as that of Neon, its closest noble gas which is 1s2 2s2 2p6. Hence the answer given above.
Elements can accept or donate electrons in order to complete their octet structure in accordance to the octet rule which states that atoms and ions must possess eight electrons in their outermost shell in order to attain chemical stability. The reason for ion formation and chemical reaction is in order for species to attain the octet structure.
Answer:
20.2 kJ
Explanation:
Based on the information in the reaction, the amount of heat released per mole of Na₂O₂ (the molar enthalpy) is calculated as follows:
126 kJ / 2 mol = 63 kJ/mol Na₂O₂
The number of moles in 25.0g of Na₂O₂ must be calculated using the molecular weight of Na₂O₂ (77.978 g/mol):
(25.0 g)/(77.978 g/mol) = 0.32060 mol Na₂O₂
Thus, the heat released will be:
(63 kJ/mol)(0.32060 mol) = 20.2 kJ
it makes aloh
AlCl3 + 3NaOH = AlOH3 + 3NaCl
Al3+ + 3Cl- + 3Na+ + 3OH- = AlOH3 + 3Na+ + 3Cl-
all cancels out except
Al3+ + 3OH- = AlOH3
