Answer:
Tests for gases
Hydrogen, oxygen, carbon dioxide, ammonia and chlorine can be identified using different tests.
Hydrogen. A lighted wooden splint makes a popping sound in a test tube of hydrogen.
Oxygen. A glowing wooden splint relights in a test tube of oxygen.
hope it will help
The answer is 28.02.
The chemical formula for cadmium nitrate is Cd(NO₃)₂.
There are in total 2 nitrogen atoms in Cd(NO₃)₂. If <span>the atomic weight of nitrogen is 14.01</span>, the mass <span>of two nitrogen atoms in one mole of cadmium nitrate is 28.02:
2 </span>· 14.01 = 28.02
Answer:
D. It is the sharing of electrons between atoms with an electronegativity difference below 1.7
Covalent bonds share electrons, whereas ionic bonds exchange electrons. Covalent bonds have an electronegativity of 0.0-1.7 (0.0-0.3 is a nonpolar covalent bond and 0.3-1.7 is a polar covalent bond). Ionic bonds are bonds that go beyond the electronegativity of 1.7 to 4.0 (1.7-4.0).
<span>when the number of moles Ca = mass of Ca / molar mass of Ca.
and we can get the molar mass of Ca, it is = 40 g/mol
and we have already the mass of Ca (given) = 9.8 g
so, by substitution: the moles Ca = 9.8 g / 40 g/mol
= 0.245 moles</span>