Answer:
That information is better presented and analyzed in a table.
This table shows you all the information and the answers:
Substance melting point boiling point room temperature conclusion
°C °C °C (state)
A 0 100 25 liquid
B 50 200 25 solid
C -150 10 25 gas
Explanation:
1) Substance A at 25° is above the melting point and below the boiling point, then it is liquid (just like water)
2) Substance B at 25°C is below the melting point, so it is solid.
3) Substance C at 25°C is above the boiling point, so it is gas.
The relative molecular mass of the gas : 64 g/mol
<h3>Further explanation</h3>
Given
Helium rate = 4x an unknown gas
Required
The relative molecular mass of the gas
Solution
Graham's Law

r₁=4 x r₂
r₁ = Helium rate
r₂ = unknown gas rate
M₁= relative molecular mass of Helium = 4 g/mol
M₂ = relative molecular mass of the gas
Input the value :

Take the attached picture of a periodic table as a guide. You are finding for a solid metal. Therefore, streamline your choices by looking at elements written in black bold letters, because they are all solid. Next, if you look at the center, the legend for metals are colors in orange, yellow, flesh, lavender, pink, and cyan blue. These region would be your choices. Next, you want to find a metal that is shiny and ductile. The shiny appearance is a common characteristic of luster by materials. Ductility is the ability of a metal to stretch when under tensile stress. These properties are best exhibited by metals in the transitions metals colored in pink. Therefore, the answer to your question would be any of the metal in the pink area. Examples are Titanium, Chromium, Gold, Silver, Platinum, Tungsten, etc.
Answer:
317.6 mL
Explanation:
Step 1: Write the balanced neutralization equation
MgO + 2 HCl ⇒ MgCl₂ + H₂O
Step 2: Calculate the mass corresponding to 640.0 mg of MgO
The molar mass of MgO is 40.30 g/mol. The moles corresponding to 640.0 mg (0.6400 g) of MgO are:
0.6400 g × (1 mol/40.30 g) = 0.01588 mol
Step 3: Calculate the moles of HCl that react with 0.01588 moles of MgO
The molar ratio of MgO to HCl is 1:2. The moles of HCl are 2/1 × 0.01588 mol = 0.03176 mol
Step 4: Calculate the volume of 0.1000 M HCl that contains 0.03176 moles
0.03176 mol × (1 L/0.1000 mol) = 0.3176 L = 317.6 mL