Answer:
the answer is d. but try 20
Explanation:
Answer:
C
Explanation:
an index fossil is a fossil from a very short-lived, geographically widespread species known to exist during a specific interval of geological time.
Answer:
7
Explanation:
cuz it is trust me hope it helps though
When a light source moves away for an observer.
Answer:
3 will be the correct coefficient of CaBr2
Explanation:
In balancing a chemical equation, numbers should be assigned to both reactants and products as a numerical coefficients until all atoms of elements in both sides of the equation count equal.
The balanced equation of the reaction will be:
3CaSO4 + 2AlBr3 ==> 3CaBr2 + Al2(SO4)3
Looking at the unbalanced equation in the question, in the product Al2(SO4)3 there are 3 SO4 group. This will warrant putting 3 behind CaSO4 in order to balance the atoms of SO4 group. That operation will automatically put the number of Ca atoms in CaSO4 to be 3 therefore making CaBr2 to have 3 coefficient as in the balanced equation. This is to balance the number of Ca atoms in both sides to be 3.