In one day the average american student is in class for 5.5 hours and inone week they are in class 1 day and 3.5 hours
We see from the chemical formula itself that there is 1
mole of F2 for every 1 mole of CaF2, hence the number of moles of CaF2 is also:
moles CaF2 = 1.23 moles
The molar mass of CaF2 is 78.07 g/mol, so the mass is:
mass CaF2 = 78.07 g / mol * 1.23 mol
<span>mass CaF2 = 96.03 grams</span>
Answer:
4.6 × 10²³ molecules:
Step-by-step solution
You will need a balanced equation with masses, moles, and molar masses, so let's gather the information in one place:
M_r: 22.99
2Na + 2H₂O ⟶ 2NaOH + H₂
m/g: 35
1. Calculate the <em>moles of Na
</em>
Moles of Na = 35 g Na × (1 mol Na/22.99 g Na)
Moles of Na = 1.52 mol Na
2. Calculate the <em>moles of H₂
</em>
Moles of H₂ = 1.52 mol Na × (1 mol H₂/2 mol Na)
Moles of H₂= 0.761 mol H₂
3. Calculate the molecules of H₂
6.022 × 10²³ molecules H₂ = 1 mol H₂
Molecules of H₂ = 0.761 × (6.022 × 10²³
/1)
Molecules of H₂ = 4.6 × 10²³ molecules H₂
The reaction forms 4.6 × 10²³ molecules of H₂.
Hello!
The concentration of the reactants decreases and the concentration of products increases during the course of a forward chemical reaction.
A chemical reaction is a thermodynamical process in which two or more substances (called reagents) undergo transformation by the breaking and rearrangement of their chemical bonds to form another substance(s), called products. In a forward chemical reaction, the reagents are being consumed, so their concentration will decrease, increasing the concentration of products as they are the result of the reaction.
The study of how concentration changes with time in a chemical reaction is called reaction kinetics.
Have a nice day!
According to Henderson–Hasselbalch Equation,
pH = pKa + log [Nitrate] / [Nitric Acid]
As, Ka of Nitric Acid = 7.1 × 10⁻⁴
So,
pKa = -log [ 7.1 × 10⁻⁴ ]
pKa = 3.148
So, pH = 3.148 + log [Nitrate] / [Nitric Acid]
3.90 = 3.148 + log [Nitrate] / [Nitric Acid]
3.90 - 3.148 = log [Nitrate] / [Nitric Acid]
0.752 = log [Nitrate] / [Nitric Acid]
Taking Antilog on both sides,
[Nitrate] / [Nitric Acid] = 5.64
