Answer:
False
Explanation:
Message me for explanation.
<em>Answer:</em>
- Element: Element are pure substance consist of same type of atoms
- Compound: Form by combination of atoms of different elements.
<em>Distinguish features:</em>
- Compounds represented by chemical formula while elements are represented by symbols.
- Compounds have fixed ratios of atoms of different elements while in elements are distinguished by atomic no.
- Compounds can be converted into simple substance by chemical methods but the elements cant be converted into simpler substance by means of chemical methods.
<em>Example:</em>
- Water (H2O) is a compounds.
- Iron (Fe) is an element.
<em>Summary:</em>
- When two or more elements are mixed then compounds are formed.
Answer:
(x+10) (x+3)
Explanation:
1) this quadratic equation is in the form of: ax^2+bx+c
where we need to figure out what*what=c(30)
and what+what=13(b)
factors of 30: -1,-30 1,30 2,15 -2,-15 3,10 -3,-10 5,6 -5,-6
factors of 30 which equal 13: 3,10
lets substitute 3 and 10 in lace of 13x to factor by grouping:
x^2+3x+10x+30
make two sets:
set a) x^2+3x
set b) 10x+30
the GCF in set a is "x":
x(x+3)
The Gcf in set b is 10:
10(x+3)
now combine the terms outside the parantheses:
(x+10)(x+3)=0
Hope this helps!
Answer:
(a) Dissolving sugar in water ⇒ physical change
(b) Crushing rock salt ⇒ physical change
(c) Burning sulfur ⇒ chemical change
(d) Digesting a chili dog ⇒ chemical change
Explanation:
<em>Physical changes</em> are those in which the substance does not alter its composition. They only involve changes of states of matter and the chemical substance is stil the same after the change occurs. By other hand, <em>chemical changes</em> are those in which new subtances are formed. So, the subtance is not the same after the change.
(a) Dissolving sugar in water ⇒ <em>physical change</em>; because we obtain a solution of sugar in water (sugar is stil sugar).
(b) Crushing rock salt ⇒ <em>physical change</em>; because we obtain crushed salt, but the chemical composition of the salt is not altered.
(c) Burning sulfur ⇒ <em>chemical change</em>; because sulfur is oxidized (chemical reaction) and new compounds are formed, for example sulfur dioxide.
(d) Digesting a chili dog ⇒ <em>chemical change</em>; because the digestion process is produced by the action of hydrocloric acid, and new compounds are formed.
