Answer:
=> 1366.120 g/mL.
Explanation:
To determine the formula to use in solving such a problem, you have to consider what you have been given.
We have;
mass (m) = 25 Kg
Volume (v) = 18.3 mL.
From our question, we are to determine the density (rho) of the rock.
The formula:

First let's convert 25 Kg to g;
1 Kg = 1000 g
25 Kg = ?

= 25000 g
Substitute the values into the formula:

= 1366.120 g/mL.
Therefore, the density (rho) of the rock is 1366.120 g/mL.
Elements are substances that contain only 1 kind of atom.
Answer:
220mol.
Explanation:
Water is H2O. Hydrogen gas is H2. Oxygen gas is O2. You have 220mol of O and 460mol of H. O is the limiting reactant. The ratio O:H2O is 1:1. 220*1=220
Answer:
6.2 calories
Explanation:
Data Given:
change in temperature = 20 °C
specific heat of gold = 0.031 calories/gram °C
mass of gold = 10.0 grams
Amount of Heat = ?
Solution:
Formula used
Q = Cs.m.ΔT
Where:
Q = amount of heat
Cs = specific heat of gold = 0.031 calories/gram °C
m = mass
ΔT = Change in temperature
Put values in above equation
Q = 0.031 calories/gram °C x 10.0 g x 20 °C
Q = 6.2 calories
So option A is correct = 6.2 calories
Answer:
The molecular formula of estradiol is:
.
Explanation:
Molar mass of of estradiol = M= 272.37 g/mol
Let the molecular formula of estradiol be 
Percentage of an element in a compound:

Percentage of carbon in estradiol :

x = 18.0
Percentage of hydrogen in estradiol :

y = 24.2 ≈ 24
Percentage of oxygen in estradiol :

z = 2
The molecular formula of estradiol is: 