Answer:
a
. eight tenths of her cookies
Explanation:
Let the total number of Lakesha's cookies be represented by x.
So that;
She gave three tenths to Bailey = 
of x
= 
She gave five tenths to Helen = 
of x
= 
Fraction of Lakesha's cookies given away = +
= 
= 
Thus, the fraction of cookies given away by Lakesha is 
.
To determine the amount of a substance in units of moles from units of grams, we need to determine the molar mass of the substance. <span>The </span>molar mass<span> is the </span>mass<span> of a given chemical element or chemical compound (g) divided by the amount of substance (mol). For CuF2, the molar mass </span><span>101.543 g/mol. We calculate as follows:
100.0 g CuF2 ( 1 mol / 101.543 g) = 0.98 mol CuF2</span>
Answer:
<u>Osmosis </u>is the process that describes water moving through a membrane.
I am not sure about the second question.
Explanation:
Answer:
A). It encouraged them to rely on observation and experimentation to support their conclusions.
Explanation:
Answer:
368.92g
Explanation:
Firstly, let's balance the equation which is
2NO + O₂ ---> 2NO₂
Starting with 8.02 mol of NO let's calculate the moles of oxygen which is in a 2 : 1 molar ratio
2NO + O₂
2 : 1
8.02 mol : x mol
Moles of O₂ = 8.02 ÷ 2 = 4.01 mol
Doing the same thing for 18.75 mol of O₂ to calculate the number of moles of NO
2NO + O₂
2 : 1
x mol : 18.75 mol
Moles of NO = 18.75 × 2 = 37.5 however we are told we have 8.02 moles of NO, so we are unable to use 18.75 mol of O₂
Using 8.02 mol of NO to figure out the number of moles of NO₂ :
2NO : 2NO₂
They have the same molar ratio of 2 : 2, so the number of moles is 8.02
Using formula moles = mass / Molar mass
Rearranging to find mass = moles × molar mass
Molar mass of NO₂ = 14 + 16 + 16 = 46
Mass = 46 × 8.02 = 368.92g
