Answer:
Density, 
Explanation:
The attached figure shows a 38.6 kg marble slab. The dimensions of the marble slab is 23 cm × 17 cm × 4 cm
Density = mass/volume
Volume of a cuboid shape is equal to, V = 23 cm × 17 cm × 4 cm
V = 1564 cm³
Density,
or
So, the density of the marble slab is 
.
Answer:
2.893 x 10⁻³ mol NaOH
[HCOOH] = 0.5786 mol/L
Explanation:
The balanced reaction equation is:
HCOOH + NaOH ⇒ NaHCOO + H₂O
At the endpoint in the titration, the amount of base added is just enough to react with all the formic acid present. So first we will calculate the moles of base added and use the molar ratio from the reaction equation to find the moles of formic acid that must have been present. Then we can find the concentration of formic acid.
The moles of base added is calculated as follows:
n = CV = (0.1088 mol/L)(26.59 mL) = 2.892992 mmol NaOH
Extra significant figures are kept to avoid round-off errors.
Now we relate the amount of NaOH to the amount of HCOOH through the molar ratio of 1:1.
(2.892992 mmol NaOH)(1 HCOOH/1 NaOH) = 2.892992 mmol HCOOH
The concentration of HCOOH to the correct number of significant figures is then calculated as follows:
C = n/V = (2.892992 mmol) / (5.00 mL) = 0.5786 mol/L
The question also asks to calculate the moles of base, so we convert millimoles to moles:
(2.892992 mmol NaOH)(1 mol/1000 mmol) = 2.893 x 10⁻³ mol NaOH
The total number of protons in Copper is 29.
The ionic compound will be soluble in water.
The value of the heat of solution of a substance is one of the factors that determine whether a substance will dissolve or not. A negative heat of solution signifies that the reaction will be spontaneous, so the ionic compound will dissolve in water.
Avagadros number states that 1 mol of any substance is made of 6.022 x 10²³ units.
These units could be atoms that make up an element or molecules that make up a compound. CO₂ is a compound therefore its made of CO₂ molecules.
1 mol of CO₂ contains 6.022 x 10²³ molecules of CO₂
Therefore if 6.022 x 10²³ molecules of CO₂ make up 1 mol
then 1.25 x 10¹⁵ molecules of CO₂ make up -
Number of CO₂ moles present - 2.0756 x 10⁻⁹ mol of CO₂
