Answer:
C) 2 Na + 2 H2O → 2 NaOH + H2.
Explanation:
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In this case, according to the given chemical reactions, it is possible to firstly understand that a single displacement reaction is characterized by the presence of a single element as the first reactant and a compound as the second one, thus, yielding a compound as the first product and a single element as the second one.
In such a way, according to the given choices, it possible to note that C) 2 Na + 2 H2O → 2 NaOH + H2 is the only one with the aforementioned condition as the element at the reactants side is Na and at the products side is H2.
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1) T<span>he dissolution of the salt potassium sulfite:
K</span>₂SO₃(aq) → 2K⁺(aq) + SO₃²⁻(aq).
Potassium has +1 charge because it lost one electron to accomplish stabile electron configuration of noble gas argon.
2) From dissolution reaction: n(K⁺) : n(SO₃²⁻) = 2 : 1.
n(K⁺) = 0.700 mol.
0.700 mol : n(SO₃²⁻) = 2 : 1.
n(SO₃²⁻) = 0.700 mol ÷ 2.
n(SO₃²⁻) = 0.350 mol; amount of sulfite anions.
Answer:
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Explanation:
2 Atom of Hydrogen are present in 2 (NaHCO3)
The initial temperature of the metal = 35 °C
<h3>Further explanation</h3>
Heat can be formulated :
Q = m . c . ΔT
Q = heat, J
c = specific heat, J/g C
ΔT = temperature, °C
m = 20 g
c = 5 J/(g°C)
Q = 500 J
T₁ = 40 C
the initial temperature :
Explanation:
Molarity = mol/L or g/L
Data:
Mass>80.0g
Mr of CaCl2>111.1g/mol
V>500mL
Convert mL to Litres;. mole=g/Mr
1L=1000mL. =80g/111.1g/mol
x=500mL. =0.720072007mol
x=0.5L
Molarity= mole/volume
=0.720072007mol/0.5L
=1.440144014mol/L
=1.4401mol/L
Hope this helps. Depending on the question you can also find it in g/L but mol/L is safer.
