Science test 10/2/19

nucleus

Rutherford predicted that an atom has a dense core called a _______

carbon has 6 protons, 6 electrons, and 6 neutrons and boron has 5 protons, 5 electrons, and 7 neutrons

a carbon atom has an atomic number of 6, and a boron atom has an atomic number of 5. an atom of carbon-12 has the same mass number of boron-12. sketch molecules that show the difference in the two atoms

number of valence electrons

all the elements in group 2 have the same...

group 18 are the only elements with 8 valence electrons the element in period 5 with 8 valence electrons is xenon

an element in period 5 has eight valence electrons. use the periodic table to figure out which element this is. explain why you chose this element

non metal

density- low; conductivity- low; appearance- dull; mallability- low; ductility- low; this element is more likely to be a _________________

by increasing atomic number

how are the atoms arranged in the modern periodic table?

8

how many valence electrons are present in an atom of argon?

density, conductivity, appearance, malleability, and ductility

if you were given 5 unknown substances and were asked to describe them by their physical properties, what would you look for? what should you not do while observing for physical properties?

8

most atoms gain, lose, or share electrons to end up with how many valence electrons?

semi conductors

one property of metalliods not shared with metals or nonmetals is the metalloids are ________________

particle excelerator

scientists learn about the properties of some particles from the collisions that occur inside ________________________

acid and base

the products of a neutralization reaction are ...

chlorine and iodine

use the periodic table to choose the pair of elements whose properties are most similar

feels slippery

what is a property of a base?

a plastic bottle

what is most likely to be damaged by an acid?

polar

when a molecule has slight positive and negative charges at different locations, the molecule is ___________

when they share electrons

when do atoms form a covalent bond?

neutron

which atomic particle has no charge?

chlorine -35, chlorine -37

which pair of atoms are isotopes?

one type of atom cannot be changed to another type by a chemical reaction

which statement is part of Dalton's atomic theory

mendeleev

who organized elements into the modern periodic table?

valence electrons are free to move

why do metals have high conductivity?