The formula for solving current given with resistance and power source or voltage is shown below:
I = V/R
When two 5 ohms resistors are in series, we have:
I = 9 volts / (5+5 ohms)
I = 0.9 amperes
When it is being added with another 7.5 resistors, we have:
I = 9 volts / (5+5+7.5 ohms)
I = 0.529 ampere
The answer to the question is the letter "D. decrease; 0.51 amps".
<span>Answer:
CH3-CH2-0-CH2-CH3
that is diethyl ether
mechanism is SN2</span>
Answer:
Single replacement reaction (aka single displacement reaction)
Explanation:
In a single replacement reaction, one element is substituted for another in a compound to create a new compound and a new element in the products. The general form is:
A + BC --> B + AC
In the case of this question, Cr and Fe "trade places."
Question #1
Potasium hydroxide (known)
volume used is 25 ml
Molarity (concentration) = 0.150 M
Moles of KOH used
0.150 × 25/1000 = 0.00375 moles
Sulfuric acid (H2SO4)
volume used = 15.0 ml
unknown concentration
The equation for the reaction is
2KOH (aq)+ H2SO4(aq) = K2SO4(aq) + 2H2O(l)
Thus, the Mole ratio of KOH to H2SO4 is 2:1
Therefore, moles of H2SO4 used will be;
0.00375 × 1/2 = 0.001875 moles
Acid (sulfuric acid) concentration
0.001875 moles × 1000/15
= 0.125 M
Question #2
Hydrogen bromide (acid)
Volume used = 30 ml
Concentration is 0.250 M
Moles of HBr used;
0.25 × 30/1000
= 0.0075 moles
Sodium Hydroxide (base)
Volume used 20 ml
Concentration (unknown)
The equation for the reaction is
NaOH + HBr = NaBr + H2O
The mole ratio of NaOH : HBr is 1 : 1
Therefore, moles of NaOH used;
= 0.0075 moles
NaOH concentration will be
= 0.0075 moles × 1000/20
= 0.375 M
The molecular weight of K2SO4 is 174.26 g/mole. The mass of K2SO4 required to make this solution is calculated in the following way.
550mL * (0.76mole/1000mL) * (174.26g/mole) = 72.84gram
<span>I hope this helps.</span>
