Answer:
313.5cm²
Explanation:
Given parameters:
Weight of model = 105pounds
Pressure applied on the scale by model = 2.16pounds per square inch
Unknown:
Area of her feet in cm² = ?
Solution:
Pressure is the force per unit area;
Pressure =
Input the parameters and solve;
2.16 =
105 = 2.16 x Area
Area = = 48.6in²
We need now to convert the in² to cm²
1in² = 6.45cm²
48.6in² = 48.6 x 6.45 = 313.5cm²
Answer:
BF₃ ⇒ 0.891
SF₄ ⇒ 0.109
Explanation:
It seems the question is incomplete, in that case I will answer using the values that have been found in simmilar questions online. If the values in your problem vary, keep that in mind when solving it.
" A 9.00 L tank at 23.6 °C is filled with 12.2 g of boron trifluoride gas and 2.37 g of sulfur tetrafluoride gas. You can assume both gases behave as ideal gases under these conditions. Calculate the mole fraction of each gas. Round each of your answers to 3 significant digits. "
First we <u>convert g of both compounds to mol</u>, using their molar mass:
- Boron trifluoride BF₃ ⇒ Molar mass = 67,82 g/mol
12.2 g ÷ 67.82 g/mol = 0.180 mol BF₃
- Sulfur tetrafluoride SF₄ ⇒ Molar mass = 108 g/mol
2.37 g ÷ 108 g/mol = 0.022 mol SF₄
Total number of moles = moles BF₃ + moles SF₄ = 0.180 + 0.022 = 0.202
Finally we calculate the mole fracion of each gas:
- BF₃ ⇒ 0.180 / 0.202 = 0.891
- SF₄ ⇒ 0.022 / 0.202 = 0.109
Ionic bonds contain atoms of metals bonded with atoms of nonmetals.