Answer:
Explanation:
Magnesium when it oxidizes has a valence of 2.
Oxygen, when it mixes with something, has a valence of - 2
So Mg and O2 will form something, but what? The answer is MgO
Mg + O2 ===> MgO
To balance this equation, you need 2 Magnesiums on the right and 2 Oxygens also on the right. The left will need a two Magnesiums.
The balanced equation will be
2Mg + O2 ====> 2MgO
Answer:
MgBr₂ + AgNO₃ => Mg(NO₃)₂ + AgBr
Explanation:
Find the element symbol and charge of each element on the periodic table. For polyatomic ions (nitrate), reference your polyatomic ions chart. Use the "partner's charge" rule to find the number of atoms in each compound.
Charges are written as superscripts. "1" is usually not written, just the + or - sign. The charge of silver is 1, which is the (I) bracket roman numeral 1. It is indicated like that because it is multivalent, meaning it has more than one possible charge.
<u>Write each element as an ion</u> (with the charge).
Magnesium is Mg²⁺
Bromide is Br⁻
Silver(I) is Ag⁺
Nitrate is (NO₃)⁻
<u>Write each compound.</u>
REACTANTS SIDE
Magnesium bromide
Mg²⁺Br⁻ Cross over the partner's charge. Since Br is charge 1, Mg has 1 atom. Since Mg has charge 2, Br has 2 atoms.
MgBr₂
Silver(I) nitrate
Ag⁺(NO₃)⁻
AgNO₃ Both have 1 atom because each partner's charge was 1. You do not need to write brackets if nitrate only has 1 atom.
PRODUCTS SIDE
Magnesium nitrate
Mg²⁺(NO₃)⁻
Mg(NO₃)₂ Nitrate has 2 atoms because magnesium's charge is 2.
Silver(I) bromide
Ag⁺Br⁻
AgBr Both have 1 atom.
Write the compounds into an equation. Reactants go on the left side, products go on the right side. Between the reactants and products, write an arrow.
MgBr₂ + AgNO₃ => Mg(NO₃)₂ + AgBr
Answer:
The process is endothermic.
Heat is 26,9 kJ/mol
Explanation:
The dissolution of NH₄NO₃ in water is:
NH₄NO₃ → NH₄⁺ + NO₃⁻
As the change of temperature in the cup is ΔT = -3,82°C
<em>The process is endothermic</em>. Because the temperature is decreasing in the process. That means the process needs heat.
Assuming the heat capacity of the solution is 4.18 J/Kg
:
q = -C×m×ΔT
Where q is heat, C is heat capacity (4,18J/Kg), m is mass (105g) and ΔT is change in temperature (-3,82°C)
q = 1677 J ≈ <em><u>1,68kJ</u></em>
The moles of NH₄NO₃ dissolved are:
5,00g × (1mol / 80,043g) = <em><u>0,0625 moles</u></em>
That means heat of this process in kJ/ mol is:
1,68kJ / 0,0625moles = <em>26,9 kJ/mol</em>
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I hope it helps!
Answer:
Therefore, none of the zeros is a significant figure and hence there is only one significant figure in this measurement in support G. The measurement is 0.7 minutes. Here again, zero is not a significant figure and therefore the only significant figure is one which is seven in support Edge.
Explanation:
