Answer:
this showed that the cathode rays traveled in straight line
The correct answer is A. <span>167 milliliters of 7% solution and 333 milliliters of 4% solution and here is how:
</span><span>If x is the number of milliliters of the 7% saline solution and y is the number of milliliters of the 4% saline solution then add up to 500 milliliters total, so x + y = 500.
</span>and if we do
x + y = 500
<span>x = 500 - y </span>
<span>0.07x + 0.04y = 25 (substitute 500 - y for x) </span>
<span>0.07(500 - y) + 0.04y = 25 </span>
<span>35 - 0.07y + 0.04y = 25 </span>
<span>-0.03y + 35 = 25 </span>
<span>-0.03y = -10 </span>
<span>y = 333.333... </span>
<span>y = about 333 </span>
<span>x = 500 - y = 500 - 333 = 167
</span>Then you know why the answer is A.
Answer:
A mixture is a combination of two or more pure substances that are not chemically combined. Mixtures are held together by physical forces and therefore can be separated physically.
If I made no mistake in calculation, the given answer must be correct...(tried my best)
elements : carbon hydrogen oxygen Fluorine
composition [C] 24 3 16 57
M r 12 1 16 19
(divide C by Mr) 2 3 1 3
(Divide by smallest value) 2 3 1 3
(smallest value = 1...so all value remained constant)
Empirical formula : C2H3OF3
if molar mas = 100 g per mole, then
first step calculate Mr. of empirical formula: [= 100]
Them molecular formula = empirical formula
