It is important to establish the true weight of the crucible because it is a necessary reference point. Later, you will be weighing the crucible to determine how much of the products are present, so it's necessary to have the true tare weight of the crucible.
<span>The crucible is heated to be sure it is free of any moisture or other volatiles that might otherwise give a misleading weight. If you start out with the crucible absolutely clean and dry, (after heating) then you know that any additional weight must have come from the sample.</span>
Answer:
the correct answer is number (1)
Explanation:
this number is the one who refers to the continental shelf because as you can see it refers to an area which is a shallow water area and near from the continent . and the continental shelf is exactly this area , it is defined as a continent which is under an area of a shallow water of the sea which we can called shelf sea
number 2 refers to continental slope and it defines as the steep slope which connect between the continental shelf and the sea floor
The formula is m = D x V
D = <span>13.69 g/cm^3.
</span>V = <span>15.0 cm^3
the mass of the liquid mercury is m= </span>13.69 g/cm^3 x 15.0 cm^3 = 195g
the molar mass of Hg is 200,
1 mole of Hg = 200g Hg, so #mole of Hg= 195 / 200 = 0.97 mol
but we know that
1 mole = 6.022 E23 atoms
0.97 mole=?
6.022 E23 atoms x 0.97 / 1 mole = 5.84 E23 atoms
Answer:
55.18 L
Explanation:
First we convert 113.4 g of NO₂ into moles, using its molar mass:
- 113.4 g ÷ 46 g/mol = 2.465 mol
Then we<u> use the PV=nRT formula</u>, where:
- P = 1atm & T = 273K (This means STP)
- R = 0.082 atm·L·mol⁻¹·K⁻¹
Input the data:
- 1 atm * V = 2.465 mol * 0.082atm·L·mol⁻¹·K⁻¹ * 273 K
And <u>solve for V</u>: