Answer:
Explanation:
Polyatomic ions are ions that contain more than one atom in each one of the ions.
Ionic compounds are made of cations (positive ions) and anions (negative ion). By convention, the cation is written before the anion.
List the ions in each compound:
<h3>CaCO₃</h3>
Cation:
,
Anion:
.
is a monatomic ion for it contains only one atom in each ion.
is a polyatomic ion for it contains four atoms (one C atom and three O atoms) in each ion.
<h3>NaF</h3>
Cation:
,
Anion:
.
Both
and
are monatomic for they contain only one atom in each ion.
<h3>FeO</h3>
Cation:
,
Anion:
.
Both
and
are monatomic for they contain only one atom in each ion.
<h3>CaCl₂</h3>
Cation:
,
Anion:
.
Both
and
are monatomic for they contain only one atom in each ion.
<h3>NaOH</h3>
Cation:
,
Anion:
.
is a monatomic ion for it contains only one atom in each ion.
is a polyatomic ion for it contains two atoms (one O atom and one H atom) in each ion.
Answer:
v = 7.95 m/s
Explanation:
Given that,
Wavelength of a wave, 
Frequency of a wave, f = 15 Hz
We need to find the speed of the wave. The speed of a wave is given by :

So, the wave move with a speed of 7.95 m/s.
We can't tell without more information. We know it will be higher than 40 and lower than 75, but we don't know exactly where it will settle. In order to work that out, we would need to know the volumes of the water and the cube, and WHAT metal the cube is made of.
Explanation:
Igneous rocks are formed by melting and cooling of magma originated from volcanic process.
when molten rock (rock liquefied by intense heat and pressure) cools to a solid state. Lava is molten rock flowing out of fissures or vents at volcanic centres (when cooled they form rocks such as basalt, rhyolite, or obsidian)
These rocks are strong, crystalline and dark in colour.