Answer: C) Elements and pure compounds are homogeneous materials because they have a uniform composition throughout.
Explanation: Element is a pure substance which is composed of atoms of similar elements. Compound is a pure substance which is made from atoms of different elements combined together in a fixed ratio by mass.
Elements are compounds form homogeneous materials as they have uniform composition throughout and the components are evenly distributed throughout the material.
Mixtures are heterogeneous materials as they do not have uniform composition and the components are not evenly distributed throughout the material.
I found number one
Atoms are not drawn to scale. Molecules of compounds have atoms of two or more different elements. For example, water (H2O) has three atoms, two hydrogen (H) atoms and one oxygen (O) atom. Methane (CH4), a common greenhouse gas, has five atoms, one of carbon (C) and four of hydrogen (H, see Fig.
Answer: 1.7 moles
Explanation:
Given that:
Volume of water V = 1.5L
(since 1 liter = 1dm3
1.5L = 1.5dm3)
Temperature T = 100°C
Convert Celsius to Kelvin
(100°C + 273 = 373K)
Pressure P = 3.5 atm
Number of moles of steam N = ?
Note that Molar gas constant R is a constant with a value of 0.0082 ATM dm3 K-1 mol-1
Then, apply ideal gas equation
pV = nRT
3.5atm x 1.5dm3 = n x (0.0082 ATM dm3 K-1 mol-1 x 373K)
5.25 = n x 3.06
n = 5.25/3.06
n = 1.7 moles
Thus, 1.7 moles of steam is present
Hey there!
Your answer is c. by the transfer of one or more electrons from one atom to another.
Ions can be positive or negative. Positive ions are called cations, and negative ions are called anions.
Electrons are transferred because two atoms have a large difference of electronegativity and the electrons are shared so unequally that the electrons are completely transferred from one atom to another, forming ions.
Hope this helps!