Which metal cations form a white precipitate with both H2SO4(aq) and Na2S2O4(aq)? 1. Ba2+ 2. Sr2+ 3. Fe2+ 4. Cu2+ it can be more than 1

1. Ba2+ 2. Sr2+

Explanation:

When a solution contains the Barium ,Ba²⁺ ion or Strontium, Sr²⁺ ion, they reacts with either H₂SO₄(aq) or Na₂SO₄(aq) to produce a white precipitate of BaSO₄(s) and SrSO₄(s) respectively

The chemical reactions are given below

Ba²⁺ +  H₂SO₄(aq) ⇒ BaSO₄(s) + 2H⁺ (aq)

Ba²⁺ +  Na₂SO₄(aq) ⇒ BaSO₄(s) + 2Na⁺ (aq)

Sr²⁺ +  H₂SO₄(aq) ⇒ SrSO₄(s) + 2H⁺ (aq)

Sr²⁺ +  Na₂SO₄(aq) ⇒ SrSO₄(s) + 2Na⁺ (aq)

first let us lay out the formula for potential

and kinetic energy:

pe = mgh

ke = (mv^2)/2

where: m=mass, v=velocity, g=gravitational

acceleration, h=height

calculating for mass using the known values of

pe:

340j = m (9.81 m/s^2) (50ft) (1m/3.28ft)

m = 2.27 kg

the law of conservation of energy states that

energy is neither created nor destroyed. therefore, the change in kinetic

energy from 50 ft to 35 ft would be equal to the change in potential energy

from 50 ft to 35 ft. however it would be opposite in signs since one is losing

while other is gaining.

ke(35ft) – ke(50ft) = - [ pe(35ft) – pe(50ft]

ke(50ft) = 0 since the brick is initially at rest

ke(35ft) = 340j - 2.27kg (9.81 m/s^2) (35ft)

(1m/3.28 ft)

ke(35ft)

= 102.38 j