A covalent bond ocurs when two elements, which are usually non-metals, share electrons<span>. an ionic bond, however, ocurs when two elements, usually a metal and a non-metal, transfer </span>electrons<span>. because of the transfer of </span>electrons<span> that occurs during ionic bonding, ionic bonds are, for the most part, much stronger, hope it helps :)</span>
Answer:
21.3 g. Option B
Explanation:
The reaction is:
4HF(g) + SiO₂(s) → SiF₄(g) + 2H₂O(g)
We analysed it and it is correctly balanced.
4 moles of hydrogen fluoride react to 1 mol of silicon dioxide in order to produce 1 mol of silicon fluoride and 2 moles of water vapor.
We determine molar mass of each reactant:
HF → 1.01 g/mol + 19 g/mol = 20.01 g/mol
SiO₂ → 16 g/mol . 2 + 28.09 g/mol = 60.09 g/mol
We convert mass to moles: 16 g . 1 mol /60.09g = 0.266 moles of glass
Ratio is 1:4. 1 mol of glass react to 4 moles of HF
Our 0.266 moles may react to (0.266 . 4) / 1 = 1.07 moles of gas
We convert moles to mass: 1.07 mol . 20.01 g/mol = 21.3 g
<h3>
Answer:</h3>
4.73 × 10^4 m
<h3>
Explanation:</h3>
From the question;
Frequency of the photon = 634 × 10^12 Hz
We are required to calculate the wavelength of the photon.
We need to know the relationship between wavelength and frequency of a wave.
The relationship between f and λ is given by;
c = fλ
Where c, is the speed of light, 2.998 × 10^8 m/s
Therefore, to get the wavelength we rearrange the formula such that;
λ = c ÷ f
= 2.998 × 10^8 m/s ÷ 634 × 10^12 Hz
= 4.73 × 10^-5 m
But we require wavelength in nm
1 M = 10^9 nm
Therefore;
Wavelength = 4.73 × 10^-5 m × 10^9 nm/m
= 4.73 × 10^4 m
Hence, the photon's wavelength is 4.73 × 10^4 m
The way scientists form a hypothesis is there is something called the scientific method. You established your question or problem first. Then you research it. You take your hypothesis, theory, or prediction of what is going to happen from your research.
Answer:
reee, here is your answer.
Explanation: CH3OH(l) + 3O2(g) rightarrow CO2(g) + 3H2O(g) CH3OH(l) + O2(g) rightarrow CO2(g) + 2H20(g) CH3OH(l) + 2O2(g) rightarrow 2CO2(g) + 4H20(g) 2CH3OH(l) + 3O2(g) rightarrow 2CO2(g) + 4H20(g) Correct Calculate Delta H degree rxn at 25 degree C.
