The temperature of the air, pavement, and the type of ice-melt compound used will affect the rate at which the ice melts. There are many different ice-melt compounds available from traditional rock salt (sodium chloride) to ice-melt pellets (calcium chloride).
Answer: someone help me with my work its so hard
Explanation:
Answer:
Ionic bond is formed by the opposite ions attraction between the 2 atoms in an ionically bonded compound. The two ions i.e. Cation and Anions are formed by oxidation and reduction reactions respectively. General Ionic formula is as follow,
Mⁿ⁺ + Nⁿ⁻ → MN
where;
Mⁿ⁺ = Cation
Nⁿ⁻ = Anion
MN = Salt
Explanation:
Ionic bond is the electrostatic forces of attraction between positively charged cations and negatively charged Anions. These forces are very stronger resulting in increasing several physical properties of Ionic compounds like melting point and boiling point e.t.c.
Example:
Sodium Chloride:
NaCl is formed by Na⁺ cation and Cl⁻ anion as follow,
Oxidation of Na;
2 Na → 2 Na⁺ + 2 e⁻
Reduction of Cl₂;
Cl₂ + 2 e⁻ → 2 Cl⁻
Crystal Lattice formation is as follow,
Na⁺ + Cl⁻ → NaCl
Answer:
energy from the sun that reaches earth
a) The reaction is exothermic since the overall enthalpy change is negative. this means that the system has lost energy to the environment, namely, the apparatus and due to drought.
b) We first calculate the number of moles in 3.55 grams of magnesium.
number of moles= mass/ atomic mass
=3.55/24
=0.1479 moles(to 4sf)
now, if 2 moles of magnesium give -1204kJ
How much energy is given by 0.1479 moles
= (0.1479×-1204kJ)
=-89.0358kJ (don't forget the negative sign)
c) two molesof MgO produces -1204kJ of energy
then -234kJ will be produced by
=(-234kJ×2moles)/1204kJ
=0.3887moles
one mole of MgO weighs 24+16=40
therefore the mass produced is 0.3887moles×40=15.548grams
(d) we first find the number of moles of MgO in 40.3 grams
number of moles=mass/RFM
=40.3g/40= 1.0075moles
if 2 moles of MgO give 1204 kJ then decomposing 1.0075 moles requires
(1.0075 moles×1204kJ)/2=606.515kJ
