Answer:
6.25 hours
Explanation:
From the question;
- Penny can knit 4 rows in 5 minutes
We need to determine the time it will take for her to knit 300 rows
4 rows = 5 minutes
300 rows = ?
= (300 × 5 ) ÷ 4
= 375 minutes
But, 1 hour = 60 minutes
Therefore;
= 375 ÷ 60
= 6.25 hours
Thus, it will take penny 6.25 hours to knit 300 rows
Answer:
Bi2(SO4)3
Explanation:
Bismuth(iii) sulfate is an ionic compound therefore, their is transfer of electron. Ionic compound has both cations and anions. The cations is positively charged ion while the anions is negatively charged ions. The cations loses electron to become positively charged while the anions gains electron to become negatively charged.
From the compound above, Bismuth(iii) sulfate the cations will be Bismuth ion which loses 3 electrons. The anions is the sulfate ion (S04)2- with a -2 charge.
The chemical formula can be computed from the charge configuration as follows
Bi3+ and (SO4)2-
cross multiply the charges living the sign behind to get the chemical formula
Bi2(SO4)3
Note the final chemical formula, the numbers are sub scripted
Pure water does
not have enough ions to conduct electricity. A mixture of metals such as iron,
zinc and copper in the wet soil can trigger electrolysis that requires excess
energy in the form of over potential to conduct electricity. The excess energy
is needed due to limited self-ionization of water. The wet soil then can
conduct current when positive and negative ions are present. The water ions begin
to flow from anode (positive electrode) to cathode (negative electrode) to be oxidize
and produce electricity.
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1) All matter is made of atoms. Atoms are indivisible and indestructible.
2) All atoms of a given element are identical in mass and properties
3) Compounds are formed by a combination of two or more different kinds of atoms.
4) A chemical reaction is a rearrangement of atoms.
1 and 2 were proved wrong.
