Answer:
Unbalanced: SiO2 + HF = SiF4 + H2O
Explanation:
Unbalanced: SiO2 + HF = SiF4 + H2O
Explanation:
A guitar string vibrates when we strikes it. It starts vibrating in several modes simultaneously. It stretches between the saddle and the nut. This distance represents one-half wavelength.
Now if we consider that the string forms a circle, then we have an interpretation of an electron which vibrates in the orbit surrounding the nucleus. We are aware that electrons have wavelength. If the circumference of the orbit happens to be the integer multiple of wavelength
, then the orbit is "allowed" since "the electron will retraces its own path."
This explains the line spectrum and not a continuous spectrum.
A line spectrum refers an electron that jumps between the specific energy levels, thus producing only specific colors.
Answer:
Explanation:
(a) Firstly, caesium abd potassium are both in Group 1 of the periodic table. Group 1 metals (also called alkali metals) are the most reactive metals of the periodic table. Caesium is more reactive than Potassium because it has a higher electropositivity than Potassium. Electropositivity is the tendency of a metal to donate electron(s) to form a cation. Electropositivity increases down the group; this is because it is easier for atoms to loose electrons on the outermost shell that are far away from the central nucleus as against atoms whose outermost electrons are closer to the central nucleus. <u>Thus, the more "bulky" an atom is, the farther it's outermost electrons (valence electrons) get from the central nucleus and the easier it is to lose the outermost electron(s). And the easier it is for the valence electron(s) to be removed, the more reactive the atom would be and vice-versa.</u>
Caesium is more reactive than potassium because it is more bulky than potassium, with an atomic number of 55, while potassium has an atomic number of 19.
NOTE: The closer an electron is to the nucleus, the more difficult it is to be removed from it's shell.
(b) i. Formula for Caesium Nitrate:
Symbol for Caesium is Cs and Nitrate is NO₃⁻.
Cs⁺ + NO₃⁻ ↔ CsNO₃
Formula for Caesium Nitrate is CsNO₃
ii. Formula for Caesium sulphate
Symbol for caesium is Cs and Sulphate is SO₄²⁻
Cs⁺ + SO₄²⁻ ↔ Cs₂SO₄
Formula for Caesium sulphate is Cs₂SO₄
NOTE: When writing the formulae, the charges would be exchanged to form the subscript as seen on the product sides above.
Answer:
54 g
Explanation:
Given data:
Mass of carbon = 18 g
Mass of CO₂ = 72 g
Mass of oxygen needed = ?
Solution:
Chemical reaction:
C + O₂ → CO₂
according to law of conservation mass, mass can neither be created nor destroyed in a chemical equation.
This law was given by French chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
In given photosynthesis reaction:
6CO₂ + 6H₂O + energy → C₆H₁₂O₆ + 6O₂
there are six carbon atoms, eighteen oxygen atoms and twelve hydrogen atoms on the both side of equation so this reaction followed the law of conservation of mass.
In a similar way,
C + O₂ → CO₂
18 g + X = 72
X = 72 -18
X = 54 g
Thus, 54 g of O₂ are required.
Population density increases
