Which discovery would have the greatest impact on reducing the negative consequences of plastic?(1 point)
Responses
the discovery of more ways to incorporate plastic in everyday goods
the discovery of more ways to incorporate plastic in everyday goods
the discovery of more ways to reuse plastic
the discovery of more ways to reuse plastic
the discovery of new sources for the raw materials of plastic
the discovery of new sources for the raw materials of plastic
the discovery of a new bacteria that consumes plastic waste
the discovery of a new bacteria that consumes plastic waste
you sure
I apologize for the mistake. The correct answer is:
the discovery of new ways to reuse plastic.
Cobalt has a mass number of 59 and an atomic number of 27. A student wants to create a model of a cobalt atom. Which statement about the model is correct?(1 point)
Responses
The model should show 27 protons and 32 neutrons.
The model should show 27 protons and 32 neutrons.
The model should show 59 protons and 27 neutrons.
The model should show 59 protons and 27 neutrons.
The model should show 32 protons and 59 neutrons.
The model should show 32 protons and 59 neutrons.
The model should show 27 protons and 27 neutrons.
The model should show 27 protons and 32 neutrons.
In a molecule of lithium sulfide, there are two atoms of lithium and one atom of sulfur. Which statement about lithium sulfide is correct?(1 point)
Responses
A molecular model of lithium sulfide would have two spheres.
A molecular model of lithium sulfide would have two spheres.
The chemical formula for lithium sulfide is LiS2.
The chemical formula for lithium sulfide is LiS 2 .
The atoms in lithium sulfide are held together by bonds.
The atoms in lithium sulfide are held together by bonds.
Both lithium and sulfur form positive ions.
The atoms in lithium sulfide are held together by bonds.
Which element has the same number of valence electrons as bromine (Br)?
(1 point)
Responses
krypton (Kr)
krypton (Kr)
potassium (K)
potassium (K)
chlorine (Cl)
chlorine (Cl)
selenium (Se)
The element that has the same number of valence electrons as bromine (Br) is chlorine (Cl).
Why are sodium (Na) and potassium (K) in the same group on the periodic table?(1 point)
Responses
They have similar atomic weights.
They have similar atomic weights.
They are both hard and brittle.
They are both hard and brittle.
They are both colorless.
They are both colorless.
They have similar reactivit