Mass/volume = density
mass = (440 mg)*(1g)/(1000mg) = 0.440g
volume = (1000cm)(1000cm)(t)
where t = thickness
density = 2.70 g/cm^3 = (0.440g)/((1000cm)(1000cm)(t))
multiply both sides by 't' and divide both sides by (2.70g/cm^3)
t = (0.440) / ((1000cm)(1000cm)(2.70)) = 1.629x10^-7 cm
t = (1.629 x 10^-7 cm)*(1000000 micrometers)/(1 cm) = 0.1629 micrometers
Answer is t = 0.1629 micrometers
1 Cal ---------- 4.184 J
? Cal ---------- 130.0 J
130.0 x 1 / 4.184 => 31.07 Cal
hope this helps!
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
Here's a short answer
Bye Felicia
<span>The molecular formula that describes the problem is
2CH3COOH (aq) + Ca(OH)2 (s) ---> Ca(CH3COO)2 (aq) + 2H2O (l)
The net equation is written as follows:
2CH3COOH- (aq) + 2H+ (aq) + Ca(OH)2 (s) ---> Ca2+ (aq) + 2 CH3COO- (aq) + 2H2O (l)
canceling out spectator ions
2H+ (aq) + Ca(OH)2 (s) ---> Ca2+ (aq) + 2 H2O (l)</span>