to help create food establishment.
Answer:
340.9°k ~ 67.8°C
Explanation:
This is an example of Gay-Lussac's law, which states that the pressure of a given amount of gas held at constant volume is directly proportional to the Kelvin temperature. This means that if the volume increases, so does the temperature, and vice versa.
The equation for this gas law is:
P1/T1 = P2/T2
Known
P1 = 198 kPa
T1 = 27°C + 273.15 = 300°K ← Temp. must be in Kelvins
P2 = 225 kPa
T2 = ?
Solution
Rearrange the equation to isolate T2
Input the known values and solve.
T2 = T1P2/P1
Where:
T2 = 300°K × 225kPa/198kPa = 340.91°K
T2 in °C = 340.91°K − 273.15 = 67.8°C
note: answers were rounded off to one decimal point.
The answer is 33.33 %
The explanation:
According to the reaction equation:
MgCO3(s) + 2HCl (aq) --> MgCl2(aq) + H20(l) + CO2(g)
we can see that 1 mole of MCO3 will produce → 1 mole of CO2
-Now we need o get number of mole of CO2:
and when we have 0.22 g of CO2, so number of mole = mass / molar mass
moles = 0.22 g / 44 g/mol = 0.005 mole
∴ moles of Mg = moles of CO2 = 0.005 mole
∴ mass of Mg = moles * molar mass
= 0.005 * 84 /mol = 0.42 g
∴ Percent of MgCO3 by mass of Mg = 0.42 g / 1.26 * 100
= 33.33 %
Answer:
pOH = 1.3, pH = 12.7
Explanation:
Since NaOH is a strong base, it will completely ionize; further, since it completely ionizes, our hydroxide concentration (a product of the ionization) will be the same as the given concentration of NaOH.
NaOH -> Na⁺ + OH⁻, [OH⁻] = 5.0 x 10^-2 M
pOH is the negative log of the hydroxide concentration, so plug our hydroxide concentration in:
pOH = -log[OH⁻] = -log[5.0 x 10^-2 M] = 1.3
Since pH + pOH = 14, we can plug in pOH and solve for pH:
pH + 1.3 = 14
pH = 14 - 1.3 = 12.7
Thus, our pOH = 1.3 and pH = 12.7.
The answer is C, because if the copper has a +2 charge, the fluoride must have a -2 charge in order to cancel out.
