Answer:
C
Explanation:
The other poster is wrong that is just a mixture, the sugar dissolved in tea tho is the right answer 90% sure
On earth, oxygen is the most common element, making up about 47% of the earth's mass. Silicon is second, making up 28%, followed by aluminum (8%), iron (5%), magnesium (2%), calcium (4%), sodium (3%), and potassium (3%). All of the remaining elements together make up less than 1% of the earth's mass.
Answer:
According to an energy pyramid model, Producer is expected have the largest biomass in land ecosystems
Explanation:
In a trophic level, the producers possess the largest biomass. With the increasing trophic level, the biomass reduces. Hence, the producers at the base have high biomass.
On terrestrial ecosystem, the producers are the plants and trees and hence the greatest biomass exists in the plants and trees.
Hence, in an energy pyramid model, Producer is expected have the largest biomass in land ecosystems
Answer:
Explanation:
a ) period 4 noble gas is krypton
isoelectronic with it are Sr ⁺² and Br⁻
compound is SrBr₂
b ) Period 3 noble gas is Argon
isoelectronic with it are Mg⁺² and O⁻²
compound is MgO
c) 2+ ion is the smallest with a filled d subshell is Zn⁺² , smallest halogen
is F⁻
compound is ZnF₂
d ) ions from the largest and smallest ionizable atoms in Period 2
Li⁺ and F⁻
compound is LiF
1) Answer is: 1,425 moles oftin(IV) chloride are formed.
Chemical reaction: 2Cl₂ + Sn → SnCl₄.
n(Cl₂) = 2,85 mol.
From chemical reaction: n(Cl₂) : n(SnCl₄) = 2 : 1.
n(SnCl₄) = n(Cl₂) ÷ 2.
n(SnCl₄) = 2,85 mol ÷ 2.
n(SnCl₄) = 1,425 mol.
n - amount of substance.
2) Answer is: mass of lithium is 128,04 grams.
Chemical reaction: 6Li + N₂ → 2Li₃N.
m(N₂) = 86,1 g.
n(N₂) = m(N₂) ÷ M(N₂).
n(N₂) = 86,1 g ÷ 28 g/mol.
n(N₂) = 3,075 mol.
From chemical reaction: n(N₂) : n(Li) = 1 : 6.
n(Li) = 6 · 3,075 mol.
n(Li) = 18,45 mol.
m(Li) = 18,45 mol · 6,94 g/mol.
m(Li) = 128,04 g.
3) Answer is: 69,77 grams of oxygen can be produced.
Chemical reaction: 2Cr(ClO₃)₃ → 2CrCl₃ + 9O₂.
m(Cr(ClO₃)₃) = 146,5 g.
n(Cr(ClO₃)₃) = m(Cr(ClO₃)₃) ÷ M(Cr(ClO₃)₃).
n(Cr(ClO₃)₃) = 146,5 g ÷ 302,35 g/mol.
n(Cr(ClO₃)₃) = 0,48 mol.
From chemical reaction: n(Cr(ClO₃)₃) : n(O₂) = 2 : 9.
n(O₂) = 2,18 mol.
m(O₂) = 2,18 mol · 32 g/mol.
m(O₂) = 69,77 g.
4) Answer is: volume of hydrogen is 97,47 dm³.
Chemical reaction: 2Al + 6H₂O → 2Al(OH)₃ + 3H₂.
m(Al) = 78,33 g.
n(Al) = m(Al) ÷ M(Al).
n(Al) = 78,33 g ÷ 27 g/mol.
n(Al) = 2,9 mol.
From chemical reaction: n(Al) : n(H₂) = 2 : 3.
n(H₂) = 2,9 mol · 3 ÷ 2.
n(H₂) = 4,35 mol.
V(H₂) = n(H₂) · Vm.
V(H₂) = 4,35 mol · 22,4 dm³/mol.
V(H₂) = 97,47 dm³ (L).
Vm - molar volume.
5) Answer is: there is 5,47·10²⁴ atoms of copper.<span>
Chemical reaction: 6Cu + N₂ → 2Cu₃<span>N.
V(N</span></span>₂) = 33,9 L.
n(N₂) = V(N₂) ÷ Vm.
n(N₂) = 33,9 L ÷ 22,4 L/mol.
n(N₂) = 1,513 mol.
From chemical reaction: n(N₂) : n(Cu) = 1 : 6.
n(Cu) = 6 · 1,513 mol.
n(Cu) = 9,08 mol.
N(Cu) = n(Cu) · Na.
N(Cu) = 9,08 mol · 6,022·10²³ 1/mol.
N(Cu) = 5,47·10²⁴.
Na - Avogadro number.