Answer :
(a) 0.0152
(b) 0.0000000778
(c) 0.000001
(d) 1600.1
Explanation :
Scientific notation : It is the representation of expressing the numbers that are too big or too small and are represented in the decimal form with one digit before the decimal point times 10 raise to the power.
For example :
5000 is written as 
889.9 is written as 
In this examples, 5000 and 889.9 are written in the standard notation and and are written in the scientific notation.
(a) 
The standard notation is, 0.0152
(b) 
The standard notation is, 0.0000000778
(c) 
The standard notation is, 0.000001
(d) 
The standard notation is, 1600.1
Answer:
the answer is 10 times
Explanation:
because it takes 10 times as much energy -3330 j - to melt 10.0 grams of ice.
V ( HCl ) = 16.4 mL / 1000 => 0.0164 L
M( HCl) = ?
V( KOH) = 12.7 mL / 1000 => 0.0127 L
M(KOH) = 0.620 M
Number of moles KOH:
n = M x V
n = 0.620 x 0.0127
n = 0.007874 moles of KOH
number of moles HCl :
<span>HCl + KOH = H2O + KCl
</span>
1 mole HCl ------ 1 mole KOH
<span>? mole HCl--------0.007874 moles KOH
</span>
moles HCl = 0.007874 * 1 / 1
= 0.007874 moles of HCl
M = n / V
M = 0.007874 / <span>0.0164
</span>= 0.480 M
Answer (2)
hope this helps!
Answer:
12.50g
Explanation:
T½ = 2.5years
No = 100g
N = ?
Time (T) = 7.5 years
To solve this question, we'll have to find the disintegration constant λ first
T½ = In2 / λ
T½ = 0.693 / λ
λ = 0.693 / 2.5
λ = 0.2772
In(N/No) = -λt
N = No* e^-λt
N = 100 * e^-(0.2772*7.5)
N = 100*e^-2.079
N = 100 * 0.125
N = 12.50g
The sample remaining after 7.5 years is 12.50g
