Explanation:
First, we need to calculate the number of moles of sodium carbonate we have in a 25 g sample. To calculate this, we will
find the molar mass of sodium carbonate (Na2CO3):
⇒ 2 × Molar mass of sodium + Molar mass of carbon + 3×molar mass of oxygen
⇒ 2 × 23 + 12 + 3 × 16
⇒ 46 + 12 + 48
⇒ 106g/mol
Thus, the molar mass of Na2CO3 is 106g/mol.
Therefore, number of moles = 25 ÷ 106
=> 0.2358 mol
Now, we know that every mole of Na2CO3 have 0.2358 moles of Na+ ions. Hence, total moles of Na2CO3 is 0.4716 moles
Number of ions present = 6.022 × 1023 × 0.4716 mol = 2.84 × 1023ions
Answer:
These predictions are likely to be valid and should be needed.
Explanation:
Meteorologist made predictions about weather of a particular area on the data they received from the satellite. Meteorology is a branch of science in which we study about the atmosphere. It is mainly used for the forecasting of weather and meteorologists are those people or scientists who study the weather and research on different scales or instruments of weather.
Answer:
CH4+2O2→CO2+2H2O
Moles of oxygen=3232=1
Moles of carbon dioxide=4422=0.5
Moles of water=1818=1
1 mole of methane reacts with 2 moles of oxygen to give 1 mole of CO2 and 2 moles of water so 0.5 mole of methane will be required which is equal to 0.5×16=8g.
Explanation:
8g
<h2>Solutions:</h2>
<u>Case a:</u> Finding pH for [H⁺] = 1.75 × 10⁻⁵ mol/L :
As we know pH is given as,
pH = -log [H⁺]
Putting value,
pH = -log [1.75 x 10⁻⁵]
pH = 4.75
<u>Case b:</u> Finding pH for [H⁺] = 6.50 × 10⁻¹⁰ mol/L :
As we know pH is given as,
pH = -log [H⁺]
Putting value,
pH = -log [6.50 × 10⁻¹⁰]
pH = 9.18
<u>Case c:</u> Finding pH for [H⁺] = 1.0 × 10⁻⁴ mol/L :
As we know pH is given as,
pH = -log [H⁺]
Putting value,
pH = -log [1.0 × 10⁻⁴]
pH = 4
<u>Case d:</u> Finding pH for [H⁺] = 1.50 × 10⁻⁵ mol/L :
As we know pH is given as,
pH = -log [H⁺]
Putting value,
pH = -log [1.50 × 10⁻⁵]
pH = 4.82
