Answer:
Explanation:
250 cm^3 of 0.2 moldm-3 H2SO4 can be prepared from 150cm^3 of 1.0 moldm^-3 by dilution.
150cm^3 of the 1.0 moldm^-3 stock solution is measured out using a measuring cylinder and transferred into a 250 cm^3 standard volumetric flask and made up to mark. The resulting solution is now 250cm^3 of 0.2 moldm-3 H2SO4.
A.) In the beginning the universe was too hot for atoms to exist.
Because choice b,c,and d are all part of the big bang theory.
Answer:
51.53 grams .
Explanation:
Na₃PO₄ ⇄ 3Na⁺¹ + PO₄⁻³ .
1 mole 3 mole
725 mL of 1.3 M Na⁺ ions
= .725 x 1.3 moles of Na⁺ ions
= .9425 moles
3 mole of Na⁺ is formed by 1 mole of Na₃PO₄
.9425 mole of Na⁺ is formed by .9425/3 mole of Na₃PO₄
Na₃PO₄ needed = .9425/3 moles = .3142 moles
Molecular weight of Na₃PO₄ = 164
grams of Na₃PO₄ needed = .3142 x 164 = 51.53 grams .
Steel is an alloy and consists of more than one element (mainly iron and carbon), therefore steel is a mixture.
